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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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No definition available.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Period of maturity of a debt security categorized as neither trading nor held-to-maturity, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value portion of cash and investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair Value Measurement, Adjusted Cost, Gross Unrealized Gains, Gross Unrealized Losses and Fair Value by Investment Category (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Adjusted Cost	$ 7,611	$ 3,135	$ 6,627	$ 8,726
Adjusted Cost	4,366	2,617
Unrealized Gains	0	0
Unrealized Losses	0	(1)
Fair Value	4,366	2,616
Adjusted Cost	9,414	4,589
Fair Value	9,414	4,588
Investments Available for Sale	$ 4,366	2,616
Minimum [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Maturities of available for sale securities	1 year
Maximum [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Maturities of available for sale securities	2 years
Cash [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Adjusted Cost	$ 5,048	1,972
Fair Value	5,048	1,972
Cash and Cash Equivalents	5,048	1,972
Mutual Funds [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Adjusted Cost	1,107	616
Unrealized Gains	0	0
Unrealized Losses	0	0
Fair Value	1,107	616
Investments Available for Sale	1,107	616
US Agency Securities [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Adjusted Cost	3,259	2,001
Unrealized Gains	0	0
Unrealized Losses	0	(1)
Fair Value	3,259	2,000
Investments Available for Sale	3,259	2,000
Recurring [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Fair Value	7,611	3,135
Fair Value	1,803	1,453
Cash and Cash Equivalents	7,611	3,135
Investments Available for Sale	1,803	1,453
Recurring [Member] \| Cash [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Fair Value	5,048	1,972
Cash and Cash Equivalents	5,048	1,972
Recurring [Member] \| Level 1 [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Fair Value	2,563	1,163
Fair Value	1,803	1,453
Cash and Cash Equivalents	2,563	1,163
Investments Available for Sale	1,803	1,453
Recurring [Member] \| Level 1 [Member] \| Mutual Funds [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Fair Value	1,107	616
Fair Value	0	0
Cash and Cash Equivalents	1,107	616
Investments Available for Sale	0	0
Recurring [Member] \| Level 1 [Member] \| US Agency Securities [Member]
Cash and available-for-sale securities adjusted cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category [Abstract]
Fair Value	1,456	547
Fair Value	1,803	1,453
Cash and Cash Equivalents	1,456	547
Investments Available for Sale	$ 1,803	$ 1,453