Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net income	$ 320,032	$ 142,891	$ 833,854
Adjustments to reconcile net income to net cash provided by operating activities:
Net gain on sale of discontinued operations, net of tax	0	0	(725,254)
Depreciation of property and equipment and amortization of other intangible assets	54,819	55,706	67,655
Stock-based compensation	33,362	43,272	52,178
Excess tax benefit associated with stock-based compensation	(18,436)	(13,420)	(131,926)
Deferred Income Tax Expense	71,800	24,779	45,466
Other, net	10,981	12,965	9,474
Changes in operating assets and liabilities
Accounts receivable	3,327	(251)	13,147
Prepaid expenses and other assets	(9,344)	7,895	19,005
Accounts payable and accrued liabilities	(12,922)	(3,469)	(48,624)
Deferred revenues	84,011	65,533	80,231
Net cash provided by operating activities	537,630	335,901	215,206
Cash flows from investing activities:
Proceeds received from divestiture of businesses, net of cash contributed and transaction costs	0	0	1,162,306
Proceeds from maturities and sales of marketable securities	1,234,156	546,006	313,817
Purchases of marketable securities	(2,622,898)	(78,975)	(787,718)
Purchases of property and equipment	(53,023)	(192,660)	(80,527)
Other investing activities	(588)	(1,129)	(4,788)
Net cash (used in) provided by investing activities	(1,442,353)	273,242	603,090
Cash flows from financing activities:
Proceeds from issuance of common stock from option exercises and employee stock purchase plans	29,303	49,983	92,510
Repurchases of common stock	(325,680)	(550,097)	(449,749)
Payments of dividends to stockholders	0	(463,498)	(518,217)
Excess tax benefit associated with stock-based compensation	18,436	13,420	131,926
Proceeds received from borrowing	0	100,000	0
Repayments of borrowings	0	(1,067)	(1,004)
Other financing activities	189	(939)	(740)
Net cash used in financing activities	(277,752)	(852,198)	(745,274)
Effect of exchange rate changes on cash and cash equivalents	(138)	(3,224)	9,440
Net (decrease) increase in cash and cash equivalents	(1,182,613)	(246,279)	82,462
Cash and cash equivalents at beginning of period	1,313,349	1,559,628	1,477,166
Cash and cash equivalents at end of period	130,736	1,313,349	1,559,628
Supplemental cash flow disclosures:
Cash paid for interest, net of capitalized interest	41,276	140,193	148,870
Cash paid for income taxes, net of refunds received	19,436	6,567	8,502
Payable to purchasers of divested businesses	$ 0	$ 0	$ (4,250)