Industry Segments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Corporate Overhead Footnote
General and administrative expense	$ 10,442	$ 8,314	$ 29,600	$ 26,964
Depreciation and amortization	855	752	2,588	2,166
Interest expense	4,155	4,219	12,391	12,713
Other general corporate (income) expense, net	279	351	1,410	14,910
Total	$ 15,731	$ 13,636	$ 45,989	$ 56,753