Condensed Consolidating Statement of Cash Flows (Detail) (USD $)	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net cash provided by (used in) operating activities	$ 91,033,000	$ 433,906,000
Cash flows from investing activities:
Additions to property, plant and equipment	(11,626,000)	(8,401,000)
Proceeds from sale of property, plant and equipment	20,000	36,000
Proceeds from sale of available-for-sale securities	1,494,000
Net cash used in investing activities	(10,112,000)	(8,365,000)
Cash flows from financing activities:
Borrowings of long-term debt	610,000,000
Repayments of long-term debt	(706,169,000)	(301,312,000)
Debt issuance costs	(11,266,000)
Repurchases of common stock	(105,856,000)	(54,623,000)
Proceeds from issuance of common stock	4,672,000	30,433,000
Net cash provided (used in) by financing activities	(208,619,000)	(325,502,000)
Effect of exchange rate changes on cash and cash equivalents	725,000	(1,177,000)
Net increase (decrease) in cash and cash equivalents	(126,973,000)	98,862,000
Cash and cash equivalents at beginning of period	245,935,000	129,846,000
Cash and cash equivalents at end of period	118,962,000	228,708,000
Parent Company
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net cash provided by (used in) operating activities	134,756,000	339,620,000
Cash flows from investing activities:
Additions to property, plant and equipment	(7,124,000)	(5,393,000)
Proceeds from sale of property, plant and equipment	20,000	36,000
Proceeds from sale of available-for-sale securities	1,494,000
Net cash used in investing activities	(5,610,000)	(5,357,000)
Cash flows from financing activities:
Cash provided by (used in) intercompany activity	(47,547,000)	90,923,000
Borrowings of long-term debt	610,000,000
Repayments of long-term debt	(706,169,000)	(301,312,000)
Debt issuance costs	(11,266,000)
Repurchases of common stock	(105,856,000)	(54,623,000)
Proceeds from issuance of common stock	4,672,000	30,433,000
Net cash provided (used in) by financing activities	(256,166,000)	(234,579,000)
Net increase (decrease) in cash and cash equivalents	(127,020,000)	99,684,000
Cash and cash equivalents at beginning of period	211,933,000	104,477,000
Cash and cash equivalents at end of period	84,913,000	204,161,000
Guarantor Subsidiaries
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net cash provided by (used in) operating activities	(45,665,000)	86,971,000
Cash flows from investing activities:
Additions to property, plant and equipment	(4,428,000)	(2,861,000)
Net cash used in investing activities	(4,428,000)	(2,861,000)
Cash flows from financing activities:
Cash provided by (used in) intercompany activity	47,547,000	(90,923,000)
Net cash provided (used in) by financing activities	47,547,000	(90,923,000)
Net increase (decrease) in cash and cash equivalents	(2,546,000)	(6,813,000)
Cash and cash equivalents at beginning of period	8,026,000	7,614,000
Cash and cash equivalents at end of period	5,480,000	801,000
Non-Guarantor Subsidiaries
Schedule of Condensed Consolidating Statement of Cash Flows [Line Items]
Net cash provided by (used in) operating activities	1,942,000	7,315,000
Cash flows from investing activities:
Additions to property, plant and equipment	(74,000)	(147,000)
Net cash used in investing activities	(74,000)	(147,000)
Cash flows from financing activities:
Effect of exchange rate changes on cash and cash equivalents	725,000	(1,177,000)
Net increase (decrease) in cash and cash equivalents	2,593,000	5,991,000
Cash and cash equivalents at beginning of period	25,976,000	17,755,000
Cash and cash equivalents at end of period	$ 28,569,000	$ 23,746,000