CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
OPERATING ACTIVITIES
Net income	$ 106,476	$ 93,187
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	16,243	14,549
Provision for doubtful accounts	3,991	6,270
Stock-based compensation	15,336	4,793
Deferred income taxes	426	6,757
Gain on divestiture	0	(1,848)
Loss on sale/disposal of assets	429	372
Changes in operating elements (net of acquisitions):
Receivables	(27,599)	(168,723)
Prepaid expenses and other	(12,639)	(16,286)
Other non-current assets	1,435	201
Accounts payable and outstanding checks	21,105	88,052
Accrued compensation and profit-sharing contribution	(64,709)	(38,008)
Accrued income taxes	48,390	32,223
Other accrued liabilities	(8,489)	(7,099)
Net cash provided by operating activities	100,395	14,440
INVESTING ACTIVITIES
Purchases of property and equipment	(3,895)	(11,124)
Purchases and development of software	(2,771)	(1,471)
Acquisitions, net of cash acquired	(369,143)	0
Restricted cash	359,388	0
Other	462	268
Net cash used for investing activities	(15,959)	(12,327)
FINANCING ACTIVITIES
Proceeds from stock issued for employee benefit plans	6,914	4,686
Stock tendered for payment of withholding taxes	(9,324)	(10,950)
Repurchase of common stock	(37,930)	(2,000)
Cash dividends	(57,335)	(52,420)
Excess tax benefit on stock-based compensation	4,842	4,253
Proceeds from short-term borrowings	2,025,000	1,225,000
Payments on short-term borrowings	(2,000,000)	(1,190,000)
Net cash used for financing activities	(67,833)	(21,431)
Effect of exchange rates on cash	(9,760)	84
Net increase (decrease) in cash and cash equivalents	6,843	(19,234)
Cash and cash equivalents, beginning of period	128,940	162,047
Cash and cash equivalents, end of period	$ 135,783	$ 142,813