Income Taxes - Deferred Income Tax Amounts Included on Consolidated Statements of Financial Position (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Current deferred income tax assets, net	$ 145,684	$ 133,151
Long-term deferred income tax liabilities, net	(29,139)	(26,807)
Total deferred income tax assets, net	$ 116,545	$ 106,344