Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$ 261,157	$ 230,843
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of fixed assets	49,729	37,448
Amortization of intangible assets	49,796	36,216
Amortization of debt issuance costs and original issue discount	2,048	1,649
Allowance for doubtful accounts	1,188	576
KSOP compensation expense	11,174	9,481
Stock based compensation	16,745	19,303
Realized loss on available-for-sale securities, net	99	338
Deferred income taxes	5,888	(526)
Loss on disposal of fixed assets	476	88
Excess tax benefits from exercised stock options	(81,689)	(55,056)
Other operating activities, net	448	215
Changes in assets and liabilities, net of effects from acquisitions:
Accounts receivable	9,475	(3,026)
Prepaid expenses and other assets	(4,727)	7,126
Income taxes	48,554	99,508
Accounts payable and accrued liabilities	12,267	3,168
Fees received in advance	43,372	39,588
Pension and postretirement benefits	(6,532)	(97,809)
Other liabilities	(33,016)	(8,133)
Net cash provided by operating activities	386,452	320,997
Cash flows from investing activities:
Acquisitions, net of cash acquired of $0 and $36,113, respectively	(983)	(743,091)
Purchase of non-controlling interest in non-public companies	0	(2,000)
Earnout payments	0	(250)
Proceeds from release of acquisition related escrows	280	0
Escrow funding associated with acquisitions	0	(37,800)
Purchases of fixed assets	(107,915)	(55,724)
Purchases of available-for-sale securities	(5,003)	(1,317)
Proceeds from sales and maturities of available-for-sale securities	5,825	1,478
Other investing activities, net	439	0
Net cash used in investing activities	(107,357)	(838,704)
Cash flows from financing activities:
Proceeds from issuance of long-term debt, net of original issue discount	0	347,224
Repayment of current portion of long-term debt	(145,000)	0
Repayment of short-term debt refinanced on a long-term basis	0	(347,224)
(Repayment) proceeds of short-term debt, net	(10,000)	462,224
Payment of debt issuance costs	0	(3,623)
Excess tax benefits from exercised stock options	81,689	55,056
Repurchase of common stock	(160,970)	(128,073)
Proceeds from stock options exercised	51,326	43,571
Other financing activities, net	(5,350)	(5,151)
Net cash (used in) provided by financing activities	(188,305)	424,004
Effect of exchange rate changes	(406)	(130)
Increase (decrease) in cash and cash equivalents	90,384	(93,833)
Cash and cash equivalents, beginning of period	89,819	191,603
Cash and cash equivalents, end of period	180,203
Supplemental disclosures:
Taxes paid	102,203	51,017
Interest paid	58,018	41,431
Noncash investing and financing activities:
Repurchase of common stock included in accounts payable and accrued liabilities	2,622	953
Deferred tax liability established on date of acquisition	(1,187)	(78,832)
Capital lease obligations	9,014	3,544
Capital expenditures included in accounts payable and accrued liabilities	2,890	998
Increase in goodwill due to acquisition related escrow distributions	$ 0	$ 4,128