Commitments and Related Party Transactions (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
---|---|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
|
Office and Aircraft Leases [Abstract] | ||||
Term of lease | 10 years | 10 years | ||
Offices [Member] | ||||
Office and Aircraft Leases [Abstract] | ||||
Operating lease expiration date | Oct. 31, 2019 | |||
K2 Investment Fund LLC [Member] | Aircraft [Member] | ||||
Office and Aircraft Leases [Abstract] | ||||
Rental fees incurred for use of aircraft | $ 579 | $ 218 | $ 1,262 | $ 690 |
Term of lease | 12 months | 12 months | ||
Rate of aircraft lease (in dollars per flight hour) | $ 8 | |||
Term of notice for cancellation of lease | 30 days |