Stockholders' Equity - Number and Cost of Employee Stock Plan Repurchases (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013
Equity [Abstract]
Employee stock plan repurchased (in shares)	265	598
Employee stock plan repurchased	$ 11,137	$ 21,366

Value of shares repurchased in connection with employee stock plans, whereby Company shares were tendered by employees for the payment of applicable withholding taxes and/or exercise price.

No definition available.

Name:	rhi_StockRepurchasedUnderEmployeeStockPlanDuringPeriodValue
Namespace Prefix:	rhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration