Consolidated Balance Sheets Balance Sheet Parenthetical (USD $)	Mar. 31, 2015	Dec. 30, 2014
Capital Unit [Line Items]
Treasury Stock, Shares	5,417,010us-gaap_TreasuryStockShares	5,260,744us-gaap_TreasuryStockShares
Common Class A [Member]
Capital Unit [Line Items]
Common Stock, Shares Authorized	112,500,000	112,500,000
Common Stock, Shares, Issued	30,729,853	30,703,472
Common Stock, Par or Stated Value Per Share	0.0001	0.0001
Common Stock, Shares, Outstanding	25,312,843	25,442,728
Common Class B [Member]
Capital Unit [Line Items]
Common Stock, Shares Authorized	10,000,000	10,000,000
Common Stock, Shares, Issued	1,381,730	1,381,865
Common Stock, Par or Stated Value Per Share	0.0001	0.0001
Common Stock, Shares, Outstanding	1,381,730	1,381,865
Preferred Stock [Member]
Capital Unit [Line Items]
Preferred Stock, Par or Stated Value Per Share	0.0001	0.0001
Preferred Stock, Shares Authorized	2,000,000	2,000,000
Preferred Stock, Shares Issued	0	0
Preferred Stock, Shares Outstanding	0	0

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Face amount or stated value per share of common stock.

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