Condensed Consolidating Financial Statements (Cash Flow) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net cash provided by operating activities	$ 229,564	$ 190,241
Cash flows from investing activities:
Capital expenditures	(24,186)	(33,124)
Payments for acquisition of a business, net of cash acquired	(354)	(6,545)
Purchases of investments	0	24,250
(Increase) decrease to investment in affiliates	0	0
Net cash used in investing activities	(24,540)	(63,919)
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	982,500	0
Principal payments on long-term debt	(728,449)	(37,000)
Payment of Promissory Note	0	(40,000)
Premium and fees paid on extinguishment of debt	(39,188)	0
Payments for financing costs	(2,070)	0
Deemed repurchases of restricted stock/units	(10,834)	(14,320)
Purchase of treasury stock	(48,227)	0
Proceeds from stock option exercises	1,216	1,031
Excess tax benefits from share-based compensation arrangements	781	4,038
Principal payments on capital lease obligations	(2,075)	(1,449)
Distributions to noncontrolling interest	(8,977)	(3,154)
Contributions from noncontrolling member	0	1,373
Net cash provided by (used in) financing activities	144,677	(89,481)
Net increase (decrease) in cash and cash equivalents from operations	349,701	36,841
Cash and cash equivalents at end of period	643,470	241,060
Effect of exchange rate changes on cash and cash equivalents	(22,552)	2,852
Consolidation, Eliminations [Member]
Cash flows from operating activities:
Net cash provided by operating activities	(370,690)	(411,248)
Cash flows from investing activities:
Capital expenditures	0	0
Payments for acquisition of a business, net of cash acquired	0	0
Purchases of investments		0
(Increase) decrease to investment in affiliates	342,031	347,025
Net cash used in investing activities	342,031	347,025
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	0
Principal payments on long-term debt	0	0
Payment of Promissory Note		0
Premium and fees paid on extinguishment of debt	0
Payments for financing costs	0
Deemed repurchases of restricted stock/units	0	0
Purchase of treasury stock	0
Proceeds from stock option exercises	0	0
Excess tax benefits from share-based compensation arrangements	0	0
Principal payments on capital lease obligations	0	0
Distributions to noncontrolling interest	0	0
Contributions from noncontrolling member		0
Net cash provided by (used in) financing activities	0	0
Net increase (decrease) in cash and cash equivalents from operations	(28,659)	(64,223)
Cash and cash equivalents at end of period	0	0
Effect of exchange rate changes on cash and cash equivalents	28,659	64,223
Parent Company [Member]
Cash flows from operating activities:
Net cash provided by operating activities	277,785	238,455
Cash flows from investing activities:
Capital expenditures	0	(3)
Payments for acquisition of a business, net of cash acquired	0	0
Purchases of investments		0
(Increase) decrease to investment in affiliates	(359,483)	(134,957)
Net cash used in investing activities	(359,483)	(134,960)
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	982,500
Principal payments on long-term debt	(728,449)	(37,000)
Payment of Promissory Note		0
Premium and fees paid on extinguishment of debt	(39,188)
Payments for financing costs	(2,070)
Deemed repurchases of restricted stock/units	(10,834)	(14,320)
Purchase of treasury stock	(48,227)
Proceeds from stock option exercises	1,216	1,031
Excess tax benefits from share-based compensation arrangements	781	4,038
Principal payments on capital lease obligations	0	0
Distributions to noncontrolling interest	0	0
Contributions from noncontrolling member		0
Net cash provided by (used in) financing activities	155,729	(46,251)
Net increase (decrease) in cash and cash equivalents from operations	74,031	57,244
Cash and cash equivalents at end of period	50,947	894
Effect of exchange rate changes on cash and cash equivalents	(23,518)	(57,931)
Guarantor Subsidiaries [Member]
Cash flows from operating activities:
Net cash provided by operating activities	306,120	169
Cash flows from investing activities:
Capital expenditures	(15,767)	(22,875)
Payments for acquisition of a business, net of cash acquired	0	0
Purchases of investments		369
(Increase) decrease to investment in affiliates	(31,090)	127,384
Net cash used in investing activities	(46,857)	104,140
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	0
Principal payments on long-term debt	0	0
Payment of Promissory Note		0
Premium and fees paid on extinguishment of debt	0
Payments for financing costs	0
Deemed repurchases of restricted stock/units	0	0
Purchase of treasury stock	0
Proceeds from stock option exercises	0	0
Excess tax benefits from share-based compensation arrangements	0	0
Principal payments on capital lease obligations	(1,208)	(1,097)
Distributions to noncontrolling interest	0	0
Contributions from noncontrolling member		0
Net cash provided by (used in) financing activities	(1,208)	(1,097)
Net increase (decrease) in cash and cash equivalents from operations	258,055	103,212
Cash and cash equivalents at end of period	434,974	122,665
Effect of exchange rate changes on cash and cash equivalents	28,659	(64,223)
Non-Guarantor Subsidiaries [Member]
Cash flows from operating activities:
Net cash provided by operating activities	16,349	362,865
Cash flows from investing activities:
Capital expenditures	(8,419)	(10,246)
Payments for acquisition of a business, net of cash acquired	(354)	(6,545)
Purchases of investments		23,881
(Increase) decrease to investment in affiliates	48,542	(339,452)
Net cash used in investing activities	39,769	(380,124)
Cash flows from financing activities:
Proceeds from the issuance of long-term debt	0
Principal payments on long-term debt	0	0
Payment of Promissory Note		(40,000)
Premium and fees paid on extinguishment of debt	0
Payments for financing costs	0
Deemed repurchases of restricted stock/units	0	0
Purchase of treasury stock	0
Proceeds from stock option exercises	0	0
Excess tax benefits from share-based compensation arrangements	0	0
Principal payments on capital lease obligations	(867)	(352)
Distributions to noncontrolling interest	(8,977)	(3,154)
Contributions from noncontrolling member		1,373
Net cash provided by (used in) financing activities	(9,844)	(42,133)
Net increase (decrease) in cash and cash equivalents from operations	46,274	(59,392)
Cash and cash equivalents at end of period	157,549	117,501
Effect of exchange rate changes on cash and cash equivalents	$ (56,352)	$ 60,783