CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowances (in dollars)	$ 5,360	$ 5,249
Other accounts receivable, allowances (in dollars)	$ 1,376	$ 1,334
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized shares	70,000,000	70,000,000
Common stock, issued shares	27,307,505	27,296,285
Treasury stock, at cost, shares	1,677,932	1,677,932