Business Acquisitions - Table (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2011 TQM [Member]	Dec. 31, 2011 GW Smith [Member]	Dec. 31, 2010 Summit [Member]	Dec. 31, 2012 NPCoil Dexter [Member]
Business Acquisition [Line Items]
Current Assets	$ 15,084	$ 8,946	$ 6,138		$ 5,536
Fixed Assets	7,177	4,308	2,869		1,211
Intangibles	9,816	3,556	6,260	17,100	3,825
Goodwill	7,893	6,773	1,120	3,423	1,786
Other Long-term Assets	1,356	1,355	1		783
Total Assets Purchased	41,326	24,938	16,388		13,141
Short-term Debt					(1,186)
Other Current Liabilities	(3,225)	(2,224)	(1,001)		(6,168)
Long-term Debt					(854)
Other Non-Current Liabilities	(6,869)	(6,869)	0		(1,258)
Present Value of Holdback	(2,623)	(1,754)	(869)		(927)
Total Liabilities Assumed	(12,717)	(10,847)	(1,870)		(10,393)
Business Acquisition Purchase Price Allocation Additional Minimum Pension Liability	987	987	0
Business Acquisition Purchase Price Allocation Equity Acquired	987	987	0
Fair Value of Previously Held Equity Interest	(4,578)	(4,578)	0
Business Acquisition, Cost of Acquired Entity, Purchase Price, Total	$ 25,018	$ 10,500	$ 14,518	$ 29,116	$ 2,748