Calculation of Earnings Per Share (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Basic earnings per common share:
Net income attributable to the Company	$ 16,075	$ 14,276	$ 52,134	$ 50,732
Increase in noncontrolling interest redemption value	(42)		(81)
Net income attributable to participating securities	(77)		(295)
Net income attributable to common shareholders	15,956	14,276	51,758	50,732
Weighted average common shares outstanding	40,739	43,182	41,248	43,710
Basic earnings per common share	$ 0.39	$ 0.33	$ 1.25	$ 1.16
Diluted earnings per common share:
Net income attributable to common shareholders	$ 15,956	$ 14,276	$ 51,758	$ 50,732
Weighted average common shares outstanding	40,739	43,182	41,248	43,710
Dilutive effect of outstanding equity awards	647	986	773	1,052
Diluted weighted average common shares outstanding	41,386	44,168	42,021	44,762
Diluted earnings per common share	$ 0.39	$ 0.32	$ 1.23	$ 1.13
Antidilutive awards excluded from computation of earnings per share	270	24	208	129