Commitments - Table of Rental Expense (Details) - USD ($) $ in Thousands  | 
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016  | 
Dec. 31, 2015  | 
Dec. 31, 2014  | 
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| Commitments and Contingencies Disclosure [Abstract] | |||
| Minimum rentals | $ 840 | $ 759 | $ 733 | 
| Less: Sublease rentals | 0 | 8 | 15 | 
| Rent expense, net | $ 840 | $ 751 | $ 718 | 
| X | ||||||||||
- References No definition available. 
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| X | ||||||||||
- Definition This element represents the payments that the lessee is obligated to make or can be required to make in connection with a property under the terms of an agreement classified as an operating lease, excluding contingent rentals and a guarantee by the lessee of the lessor's debt and the lessee's obligation to pay (apart from the rental payments) executory costs such as insurance, maintenance, and taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- Definition Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- Definition The total amount of sublease rental income recognized during the period that reduces the entity's rent expense incurred under operating leases. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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