Commitments and Related Party Transactions (Details) - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | ||
---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 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 | $ 75 | $ 213 | $ 683 | $ 472 |
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 |