Guarantees and Long Term Standby Purchase Commitments - Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Off-Balance Sheet Guarantees [Abstract]
Operating Leases, Rent Expense, Net	$ 1,300	$ 1,300	$ 1,300
Contractual Obligation, Due in Next Fiscal Year	1,455	1,063
Contractual Obligation, Due in Second Year	1,447	481
Contractual Obligation, Due in Third Year	1,439	488
Contractual Obligation, Due in Fourth Year	1,427	498
Contractual Obligation, Due in Fifth Year	1,459	193
Contractual Obligation, Due after Fifth Year	4,069	0
Contractual Obligation	$ 11,296	$ 2,723