CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 29, 2012	Dec. 31, 2011
Allowance on trade accounts receivable	$ 8,299	$ 6,591
Allowance on other receivables	4,951	5,384
Accumulated depreciation and amortization on operating property	$ 154,657	$ 145,804
Common stock, par value	$ 0.01	$ 0.01
Common stock, authorized shares	160,000,000	160,000,000
Common stock, issued shares	66,855,922	66,602,486
Treasury stock, shares	20,386,462	19,882,289