Income Taxes (Deferred Tax Assets and Liabilities by Balance Sheet Classification (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Assets and Liabilities by Balance Sheet Classification [Abstract]
Deferred tax assets	$ 252,396	$ 215,196
Deferred tax liabilities	(2,578)	(3,903)
Total net deferred tax assets	$ 249,818	$ 211,293