Income Taxes Reconciliation of income tax expense and rate based on the U.S. statutory rate to the Companys income tax expense (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Income tax expense based on the U.S. statutory rate		$ (11,015)	$ (9,987)	$ 1,805
State income taxes, net of federal tax benefit		(544)	(483)	(60)
Permanent items		243	247	658
Effect of foreign operations		(431)	304	(809)
Net change in uncertain tax positions		0	(201)	0
Change in valuation allowance - foreign loss carryforwards	$ 8,864	11,047	14,963	70
Stock-based compensation		633	113	563
Other		169	(425)	(86)
Income tax expense		$ 102	$ 8,551	$ 2,141
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Income tax expense based on the U.S. statutory rate (as a percentage)		35.00%	35.00%	35.00%
State income taxes, net of federal tax benefit, as a percentage		1.70%	1.70%	(1.20%)
Permanent items, as a percentage		(0.80%)	(0.90%)	12.80%
Effect of foreign operations, as a percenage		1.40%	(1.10%)	(15.70%)
Net change in uncertain tax positions, as a percentage		0.00%	0.70%	0.00%
Change in valuation allowance - foreign loss carryforwards, as a percentage		(35.10%)	(52.40%)	1.40%
Stock-based compensation, as a percentage		(2.00%)	(0.40%)	10.90%
Other, as a perentage		(0.50%)	1.50%	(1.70%)
Income tax expense, as a percentage		(0.30%)	(30.00%)	41.50%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount		$ 0	$ 4,020	$ 0
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Percent		0.00%	(14.10%)	0.00%