Industry Segments (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Corporate Overhead Footnote
General and administrative expense	$ 10,064	$ 10,364	$ 21,458	$ 20,275
Depreciation and amortization	527	579	1,081	1,160
Interest expense	4,610	4,090	9,141	8,242
Other general corporate (income) expense, net	718	632	1,280	1,194
Total	$ 15,919	$ 15,665	$ 32,960	$ 30,871