Goodwill and Intangible Assets Intangibles (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years 10 months 5 days
Gross Carrying Amount	$ 131,107	$ 132,703
Accumulated Amortization	61,618	50,226
Transtar
Finite-Lived Intangible Assets [Line Items]
Date of acquisition	Sep. 05, 2006
Tube Supply
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	11 years 5 months
Date of acquisition	Dec. 15, 2011
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	11 years 3 months 15 days
Gross Carrying Amount	117,794	119,118
Accumulated Amortization	55,157	45,317
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years
Gross Carrying Amount	3,888	3,888
Accumulated Amortization	3,569	3,235
Trade name
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	9 years 6 months 29 days
Gross Carrying Amount	8,025	8,297
Accumulated Amortization	1,939	1,188
Developed technology
Finite-Lived Intangible Assets [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years
Gross Carrying Amount	1,400	1,400
Accumulated Amortization	$ 953	$ 486