Equity - Earnings Per Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 24, 2016	Sep. 26, 2015	Sep. 24, 2016	Sep. 26, 2015
Numerator:
Income from continuing operations, net of income taxes	$ 37,691	$ 37,901	$ 110,811	$ 118,774
Less: Income (loss) from discontinued operations, net of income taxes	342	(34)	328	(48)
Less: Net income attributable to noncontrolling interests	298	488	1,054	1,297
Net income attributable to common shareholders	$ 37,735	$ 37,379	$ 110,085	$ 117,429
Denominator:
Weighted-average shares outstanding—Basic (in shares)	47,160	46,290	46,954	46,572
Effect of dilutive securities:
Stock options, restricted stock units, performance share units and restricted stock (in shares)	874	955	884	1,012
Weighted-average shares outstanding—Diluted (in shares)	48,034	47,245	47,838	47,584