Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 77,922us-gaap_NetIncomeLoss	$ 61,551us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of intangible assets	0us-gaap_AmortizationOfIntangibleAssets	333us-gaap_AmortizationOfIntangibleAssets
Depreciation expense	13,006us-gaap_Depreciation	12,200us-gaap_Depreciation
Stock-based compensation expense—restricted stock and stock units	8,843us-gaap_RestrictedStockExpense	8,774us-gaap_RestrictedStockExpense
Excess tax benefits from stock-based compensation	(4,256)	(707)
Deferred income taxes	8,039us-gaap_DeferredIncomeTaxExpenseBenefit	2,710us-gaap_DeferredIncomeTaxExpenseBenefit
Provision for doubtful accounts	2,551us-gaap_ProvisionForDoubtfulAccounts	3,456us-gaap_ProvisionForDoubtfulAccounts
Changes in assets and liabilities:
Increase in accounts receivable	(22,431)	(38,909)
Decrease in accounts payable, accrued expenses, accrued payroll and benefit costs	(23,234)	(14,230)
Increase in income taxes payable	37,504	31,320
Change in other assets, net of change in other liabilities	(13,464)	(7,273)
Net cash flows provided by operating activities	84,480	59,225
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures	(13,346)	(12,443)
Payments to trusts for employee deferred compensation plans	(7,455)	(5,283)
Net cash flows used in investing activities	(20,801)	(17,726)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repurchases of common stock	(59,196)	(35,025)
Cash dividends paid	(27,375)us-gaap_PaymentsOfDividends	(24,394)us-gaap_PaymentsOfDividends
Payments for notes payable and other indebtedness	(34)us-gaap_ProceedsFromRepaymentsOfDebt	(31)us-gaap_ProceedsFromRepaymentsOfDebt
Excess tax benefits from stock-based compensation	4,256	707
Proceeds from exercises of stock options	1,113	8,676
Net cash flows used in financing activities	(81,236)	(50,067)
Effect of exchange rate changes on cash and cash equivalents	(8,677)	541
Net decrease in cash and cash equivalents	(26,234)	(8,027)
Cash and cash equivalents at beginning of period	287,119	275,764
Cash and cash equivalents at end of period	260,885	267,737
Stock Repurchases Awaiting Settlement	$ 11,308rhi_StockRepurchasesAwaitingSettlement	$ 8,266rhi_StockRepurchasesAwaitingSettlement

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