Equity-Based Compensation (Summary of Sar Activity) (Detail) (USD $)	9 Months Ended
	Sep. 29, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Outstanding at beginning of year	1,702,650
Shares, Granted	0
Shares, Exercised	(102,230)
Shares, Forfeited	(1,663)
Shares, Expired	(20,341)
Shares, Outstanding at end of period	1,578,416
Shares, Exercisable at end of period	1,572,730
Intrinsic value of exercised options	$ 1,090,858
Weighted-Average Exercise Price, Outstanding at beginning of year	$ 40.43
Weighted-Average Exercise Price, Granted	$ 0.00
Weighted-Average Exercise Price, Exercised	$ 27.26
Weighted-Average Exercise Price, Forfeited	$ 36.36
Weighted-Average Exercise Price, Expired	$ 43.63
Weighted-Average Exercise Price, Outstanding at end of period	$ 41.24
Weighted-Average Exercise Price, Exercisable at end of period	$ 41.32
Stock Option And Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, Outstanding at beginning of year	1,287,724
Shares, Granted	428,987
Shares, Exercised	(64,582)
Shares, Forfeited	(35,725)
Shares, Expired	(2,011)
Shares, Outstanding at end of period	1,614,393
Shares, Exercisable at end of period	553,996
Intrinsic value of exercised options	$ 953,020
Weighted-Average Exercise Price, Outstanding at beginning of year	$ 28.91
Weighted-Average Exercise Price, Granted	$ 38.51
Weighted-Average Exercise Price, Exercised	$ 23.05
Weighted-Average Exercise Price, Forfeited	$ 34.30
Weighted-Average Exercise Price, Expired	$ 41.57
Weighted-Average Exercise Price, Outstanding at end of period	$ 31.56
Weighted-Average Exercise Price, Exercisable at end of period	$ 26.48