Significant Accounting Policies Cash Reconciliation (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash Reconciliation [Abstract]
Cash and cash equivalents	$ 22,058	$ 32,838
Long-term restricted cash equivalents	6,336	0
Total cash, cash equivalents and restricted cash equivalents	$ 28,394	$ 32,838	$ 111,897	$ 139,318