Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes
Tax reserves related to current year uncertain tax positions		$ 600
Tax reserves related to prior year uncertain tax positions		6,400
Accrued interest related to prior year uncertain tax positions		3,700
Previously recorded tax reserves for uncertain tax positions that have settled and/or closed		1,000
Net tax expense in connection with uncertain tax positions		1,800
Tax positions that, if reversed, would affect the effective tax rate		10,000	$ 10,700
Currency translation gains		3,000	2,500
Interest and penalties recognized, net of deferred taxes		1,400	1,100
Reductions in previously accrued interest and penalties		700
Income tax examinations
Prepaid income taxes		48,900	34,200
Unrecognized tax benefits		2,198	$ 7,036	$ 21,564
Forecast
Income tax examinations
Estimate payment for tax examination	$ 4,000
Other Liabilities
Income tax examinations
Unrecognized tax benefits		4,000
Other Assets
Income tax examinations
Unrecognized tax benefits		$ 1,800