Unrestricted Subsidiaries (Results of Operations) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Total revenues	$ 273,174	$ 211,800	$ 527,843	$ 412,302
Cost of revenues	43,159	35,591	83,969	69,878
Gross profit	230,015	176,209	443,874	342,424
Selling and Marketing Expense	80,862	48,617	158,339	96,729
Research and Development Expense	11,555	9,213	23,307	18,201
General and Administrative Expense	79,038	59,434	155,693	115,211
Total operating expenses	171,455	117,264	337,339	230,141
Income from operations	58,560	58,945	106,535	112,283
Interest (income) expense, net	13,670	10,301	26,079	20,534
Other expense (income), net	4,227	(213)	4,551	(87)
Income (loss) before income taxes	40,663	48,857	75,905	91,836
Income tax expense	9,287	15,087	18,709	28,123
Net Income (Loss) Attributable to Parent	31,376	33,770	57,196	63,713
Unrestricted Subsidiaries [Member]
Total revenues	128,474	69,385	241,606	131,842
Cost of revenues	13,231	5,560	24,943	10,871
Gross profit	115,243	63,825	216,663	120,971
Selling and Marketing Expense	58,532	27,244	113,858	53,705
Research and Development Expense	5,759	3,169	11,258	5,652
General and Administrative Expense	42,311	23,706	88,158	46,524
Total operating expenses	106,602	54,119	213,274	105,881
Income from operations	8,641	9,706	3,389	15,090
Interest (income) expense, net	14,420	4,486	28,031	8,613
Other expense (income), net	744	315	120	487
Income (loss) before income taxes	(6,523)	4,905	(24,762)	5,990
Income tax expense	774	1,691	1,857	2,271
Net Income (Loss) Attributable to Parent	$ (7,297)	$ 3,214	$ (26,619)	$ 3,719