Significant Accounting Policies Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt, Long-term and Short-term, Combined Amount	$ 207,059	$ 190,966
Previous Accounting Guidance [Member]
Debt, Long-term and Short-term, Combined Amount		195,700
Adjustments for New Accounting Pronouncement [Member]
Other Long-term Debt		$ 191,000