Income Taxes - Additional Disclosures (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Contingency [Line Items]
Unrecognized tax benefits	$ 17,133	$ 21,759	$ 23,966	$ 25,135
Unrecognized tax benefits, income tax penalties and interest accrued	2,900	3,100
Other Noncurrent Liabilities [Member]
Income Tax Contingency [Line Items]
Unrecognized tax benefits	$ 16,400	$ 21,800