Provision for Income Taxes Valuation allowance for deferred tax assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Valuation Allowance [Line Items]
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	$ 3,870	$ 2,378
Deferred Tax Assets, Valuation Allowance	(40,484)	(10,077)	$ (9,216)	$ (6,980)
Valuation Allowances and Reserves, Additions for Charges to Cost and Expense	(29,307)	(861)	(2,236)
Valuation Allowances and Reserves, Additions for Charges to Other Accounts	$ (1,100)	$ 0	$ 0