UNAUDITED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Account Receivable, allowances aggregating	$ 22,791	$ 18,106
Closure and post-closure liabilities, current portion	3,839	5,884
Remedial liabilities, less current portion of $28,903 and $23,587, respectively	$ 28,903	$ 23,587
Common stock, $.01 par value:	$ 0.01	$ 0.01
Common stock, authorized shares	80,000,000	80,000,000
Common stock, issued shares	59,947,866	60,672,180
Common stock, outstanding shares	59,947,866	60,672,180