Condensed Consolidating Financial Statements Condensed Consolidating Statement Of Cash Flows (Details) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Net cash provided by operating activities	$ 105,009,000	$ 118,423,000
Investment in property and equipment	(26,442,000)	(12,525,000)
Equity method investments	(3,761,000)	(9,454,000)
Issuance of mezzanine and other notes receivable	0	(4,236,000)
Collections of mezzanine and other notes receivable	224,000	110,000
Purchases of investments, employee benefit plans	(1,845,000)	(1,191,000)
Proceeds from sales of investments, employee benefit plans	4,052,000	10,909,000
Other items, net	(578,000)	(322,000)
Net cash provided (used) in investing activities	(28,350,000)	(16,709,000)
Net repayments pursuant to revolving credit facilities	27,500,000	(16,725,000)
Proceeds from issuance of long-term debt	3,360,000	543,500,000
Principal payments on long-term debt	(6,158,000)	(502,000)
Purchase of treasury stock	(3,684,000)	(22,227,000)
Dividends paid	(22,026,000)	(632,751,000)
Excess tax benefits from stock-based compensation	1,216,000	793,000
Debt issuance costs	0	(4,753,000)
Proceeds from exercise of stock options	6,677,000	4,695,000
Net cash provided (used) by financing activities	(48,115,000)	(94,520,000)
Net change in cash and cash equivalents	28,544,000	7,194,000
Effect of foreign exchange rate changes on cash and cash equivalents	(1,583,000)	813,000
Cash and cash equivalents at beginning of period	134,177,000	107,057,000
Cash and cash equivalents at end of period	161,138,000	115,064,000
Parent [Member]
Net cash provided by operating activities	60,070,000	87,072,000
Investment in property and equipment	(4,083,000)	(7,126,000)
Equity method investments	0	0
Issuance of mezzanine and other notes receivable	0	(4,236,000)
Collections of mezzanine and other notes receivable	224,000	110,000
Purchases of investments, employee benefit plans	0	0
Proceeds from sales of investments, employee benefit plans	0	0
Advances to and investments in affiliates	(1,000,000)	0
Other items, net	(578,000)	(322,000)
Net cash provided (used) in investing activities	(5,437,000)	(11,574,000)
Net repayments pursuant to revolving credit facilities	(27,500,000)	16,725,000
Proceeds from issuance of long-term debt	0	543,500,000
Principal payments on long-term debt	(5,625,000)	0
Purchase of treasury stock	(3,684,000)	(22,227,000)
Dividends paid	(22,026,000)	(632,751,000)
Excess tax benefits from stock-based compensation	26,000	183,000
Debt issuance costs		(4,753,000)
Proceeds from contributions from affiliates	0	0
Proceeds from exercise of stock options	6,677,000	4,695,000
Net cash provided (used) by financing activities	(52,132,000)	(94,628,000)
Net change in cash and cash equivalents	2,501,000	(19,130,000)
Effect of foreign exchange rate changes on cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	8,420,000	23,370,000
Cash and cash equivalents at end of period	10,921,000	4,240,000
Guarantor Subsidiaries [Member]
Net cash provided by operating activities	18,718,000	4,941,000
Investment in property and equipment	(22,182,000)	(5,217,000)
Equity method investments	(1,481,000)	0
Issuance of mezzanine and other notes receivable	0	0
Collections of mezzanine and other notes receivable	0	0
Purchases of investments, employee benefit plans	(1,845,000)	(1,191,000)
Proceeds from sales of investments, employee benefit plans	4,052,000	10,909,000
Advances to and investments in affiliates	(1,280,000)	(9,721,000)
Other items, net	0	0
Net cash provided (used) in investing activities	(22,736,000)	(5,220,000)
Net repayments pursuant to revolving credit facilities	0	0
Proceeds from issuance of long-term debt	3,360,000	0
Principal payments on long-term debt	(502,000)	(488,000)
Purchase of treasury stock	0	0
Dividends paid	0	0
Excess tax benefits from stock-based compensation	1,190,000	610,000
Debt issuance costs		0
Proceeds from contributions from affiliates	0	0
Proceeds from exercise of stock options	0	0
Net cash provided (used) by financing activities	4,048,000	122,000
Net change in cash and cash equivalents	30,000	(157,000)
Effect of foreign exchange rate changes on cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	407,000	432,000
Cash and cash equivalents at end of period	437,000	275,000
Non-Guarantor Subsidiaries [Member]
Net cash provided by operating activities	26,221,000	26,410,000
Investment in property and equipment	(177,000)	(182,000)
Equity method investments	(2,280,000)	(9,454,000)
Issuance of mezzanine and other notes receivable	0	0
Collections of mezzanine and other notes receivable	0	0
Purchases of investments, employee benefit plans	0	0
Proceeds from sales of investments, employee benefit plans	0	0
Advances to and investments in affiliates	0	0
Other items, net	0	0
Net cash provided (used) in investing activities	(2,457,000)	(9,636,000)
Net repayments pursuant to revolving credit facilities	0	0
Proceeds from issuance of long-term debt	0	0
Principal payments on long-term debt	(31,000)	(14,000)
Purchase of treasury stock	0	0
Dividends paid	0	0
Excess tax benefits from stock-based compensation	0	0
Debt issuance costs		0
Proceeds from contributions from affiliates	2,280,000	9,721,000
Proceeds from exercise of stock options	0	0
Net cash provided (used) by financing activities	2,249,000	9,707,000
Net change in cash and cash equivalents	26,013,000	26,481,000
Effect of foreign exchange rate changes on cash and cash equivalents	(1,583,000)	813,000
Cash and cash equivalents at beginning of period	125,350,000	83,255,000
Cash and cash equivalents at end of period	149,780,000	110,549,000
Eliminations [Member]
Net cash provided by operating activities	0	0
Investment in property and equipment	0	0
Equity method investments	0	0
Issuance of mezzanine and other notes receivable	0	0
Collections of mezzanine and other notes receivable	0	0
Purchases of investments, employee benefit plans	0	0
Proceeds from sales of investments, employee benefit plans	0	0
Advances to and investments in affiliates	2,280,000	9,721,000
Other items, net	0	0
Net cash provided (used) in investing activities	2,280,000	9,721,000
Net repayments pursuant to revolving credit facilities	0	0
Proceeds from issuance of long-term debt	0	0
Principal payments on long-term debt	0	0
Purchase of treasury stock	0	0
Dividends paid	0	0
Excess tax benefits from stock-based compensation	0	0
Debt issuance costs		0
Proceeds from contributions from affiliates	(2,280,000)	(9,721,000)
Proceeds from exercise of stock options	0	0
Net cash provided (used) by financing activities	(2,280,000)	(9,721,000)
Net change in cash and cash equivalents	0	0
Effect of foreign exchange rate changes on cash and cash equivalents	0	0
Cash and cash equivalents at beginning of period	0	0
Cash and cash equivalents at end of period	0	0
Consolidated [Member]
Net cash provided by operating activities	105,009,000	118,423,000
Investment in property and equipment	(26,442,000)	(12,525,000)
Equity method investments	(3,761,000)	(9,454,000)
Issuance of mezzanine and other notes receivable	0	(4,236,000)
Collections of mezzanine and other notes receivable	224,000	110,000
Purchases of investments, employee benefit plans	(1,845,000)	(1,191,000)
Proceeds from sales of investments, employee benefit plans	4,052,000	10,909,000
Advances to and investments in affiliates	0	0
Other items, net	(578,000)	(322,000)
Net cash provided (used) in investing activities	(28,350,000)	(16,709,000)
Net repayments pursuant to revolving credit facilities	(27,500,000)	16,725,000
Proceeds from issuance of long-term debt	3,360,000	543,500,000
Principal payments on long-term debt	(6,158,000)	(502,000)
Purchase of treasury stock	(3,684,000)	(22,227,000)
Dividends paid	(22,026,000)	(632,751,000)
Excess tax benefits from stock-based compensation	1,216,000	793,000
Debt issuance costs		(4,753,000)
Proceeds from contributions from affiliates	0	0
Proceeds from exercise of stock options	6,677,000	4,695,000
Net cash provided (used) by financing activities	(48,115,000)	(94,520,000)
Net change in cash and cash equivalents	28,544,000	7,194,000
Effect of foreign exchange rate changes on cash and cash equivalents	(1,583,000)	813,000
Cash and cash equivalents at beginning of period	134,177,000	107,057,000
Cash and cash equivalents at end of period	$ 161,138,000	$ 115,064,000