Calculation of Earnings Per Share (Details 1) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2015	Sep. 28, 2014	Sep. 27, 2015	Sep. 28, 2014
Basic earnings per common share:
Net income attributable to the Company	$ 17,971	$ 16,075	$ 50,987	$ 52,134
Decrease (increase) in noncontrolling interest redemption value	49	(42)	192	(81)
Net income attributable to participating securities	(73)	(77)	(223)	(295)
Net income attributable to common shareholders	$ 17,947	$ 15,956	$ 50,956	$ 51,758
Weighted average common shares outstanding	39,394	40,739	39,640	41,248
Basic earnings per common share	$ 0.46	$ 0.39	$ 1.29	$ 1.25
Diluted earnings per common share:
Net income attributable to common shareholders	$ 17,947	$ 15,956	$ 50,956	$ 51,758
Weighted average common shares outstanding	39,394	40,739	39,640	41,248
Dilutive effect of outstanding equity awards	501	647	570	773
Diluted weighted average common shares outstanding	39,895	41,386	40,210	42,021
Diluted earnings per common share	$ 0.45	$ 0.39	$ 1.27	$ 1.23
Weighted average antidilutive awards excluded from computation of earnings per share	219	270	234	208