Annual report pursuant to Section 13 and 15(d)

Subsequent Events - Additional Information (Details)

v2.4.1.9
Subsequent Events - Additional Information (Details) (USD $)
Nov. 15, 2012
Oct. 26, 2011
Feb. 11, 2015
Subsequent Event [Line Items]      
Amount authorized for repurchase of common stock $ 50,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1 $ 50,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1  
Common Stock | Subsequent event      
Subsequent Event [Line Items]      
Stock repurchase program, remaining authorization amount     18,100,000us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember
Re-Authorization of Share Repurchase Program, February 2015 | Common Stock | Subsequent event      
Subsequent Event [Line Items]      
Amount authorized for repurchase of common stock     $ 50,000,000us-gaap_StockRepurchaseProgramAuthorizedAmount1
/ us-gaap_ShareRepurchaseProgramAxis
= rrgb_ReAuthorizationofShareRepurchaseProgramFebruary2015Member
/ us-gaap_StatementClassOfStockAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsequentEventTypeAxis
= us-gaap_SubsequentEventMember