Restructuring and Other Charges (Details Textual) (USD $)	9 Months Ended	12 Months Ended
	Sep. 30, 2012 employees	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Restructuring and Other Charges (Textual) [Abstract]
Number of positions eliminated as part of work force reductions	350
Pre-tax restructuring charge		$ 7,000,000	$ 4,000,000
Restructuring and other charges (recoveries), net		8,070,000	3,655,000	0
Hill Hire contract termination [Member]
Restructuring and Other Charges (Textual) [Abstract]
Restructuring and other charges (recoveries), net	1,000,000