Consolidated Financial Statements Consolidated Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
	Mar. 31, 2017	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
New Accounting Pronouncement, Early Adoption [Line Items]
Increase in operating expenses		$ 30,000	$ 15,000
Other current payables and accrued expenses		(3,099)	13,400
Other assets		(18,007)	(4,054)
Tax assessment reserve	$ 5,400
Net cash provided by operating activities		57,921	172,296
Excess tax benefit, amount		3,200	4,200	$ 5,300
Proceeds from sale of finance receivables		4,700	17,700
Restatement Adjustment [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Other current payables and accrued expenses			(5,400)
Other assets			5,400
Accounting Standards Update 2016-09, Statutory Tax Withholding Component [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Net cash provided by operating activities		11,500	13,300
Accounting Standards Update 2016-09, Excess Tax Benefit Component [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Net cash provided by operating activities		3,200	$ 4,400
Retained Earnings [Member] | Adjustments for New Accounting Pronouncement [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Cumulative effect				$ 33,000
Other income (expense), net [Member]
New Accounting Pronouncement, Early Adoption [Line Items]
Gain from foreign currency exchange		$ 12,200