Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 24, 2016	Dec. 26, 2015
Allowance on trade accounts receivable	$ 4,881	$ 4,327
Allowance on other receivables	4,871	4,143
Accumulated depreciation and amortization on operating property	$ 187,566	$ 182,591
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	160,000,000	160,000,000
Common stock, issued shares	67,522,281	67,391,616
Treasury stock, shares	25,747,002	24,972,079