Goodwill and Other Intangibles Goodwill and Intangible Asset Rollforward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013	Jun. 30, 2013	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2013	Mar. 31, 2012
Goodwill and Intangible Assets [Line Items]
Unamortizable Goodwill	$ 2,794	$ 2,794	$ 2,794	$ 2,794	$ 2,794	$ 2,794
Gross balance						60,975
Amortizable Intangibles, Accumulated amortization						(25,110)
Net balance	30,269	31,471	34,589	35,865	34,589
Additions	342	221	247	22	707
Amortizable Intangibles, Amortization expense	(1,363)	(1,423)	(1,311)	(1,298)	(2,761)
Amortizable Intangibles, Net	26,454
Net balance	29,248	30,269	33,525	34,589	31,471
Customer Relationships Intangible [Member]
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years	11 years 6 months
Amortizable Intangibles, Gross carrying amount						33,700
Amortizable Intangibles, Accumulated amortization						(11,584)
Amortizable Intangibles, Net	20,010	20,431	21,695	22,116	21,695
Amortizable Intangibles, Amortization expense	(422)	(421)	(422)	(421)	(842)
Amortizable Intangibles, Net	19,588	20,010	21,273	21,695	20,431
Production and Supply Contract Intangibles [Member]
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years	2 years 6 months
Amortizable Intangibles, Gross carrying amount						7,893
Amortizable Intangibles, Accumulated amortization						(3,043)
Amortizable Intangibles, Net	4,040	4,236	4,735	4,850	4,735
Amortizable Intangibles, Amortization expense	(237)	(196)	(127)	(115)	(372)
Amortizable Intangibles, Net	3,803	4,040	4,608	4,735	4,236
Internally Developed Software Intangible [Member]
Goodwill and Intangible Assets [Line Items]
Weighted average remaining useful life in years	6 months
Amortizable Intangibles, Gross carrying amount						16,588
Amortizable Intangibles, Accumulated amortization						(10,483)
Amortizable Intangibles, Net	3,425	4,010	5,365	6,105	5,365
Additions	342	221	247	22	707
Amortizable Intangibles, Amortization expense	(704)	(806)	(762)	(762)	(1,547)
Amortizable Intangibles, Net	3,063	3,425	4,850	5,365	4,010
All Other Segments [Member]
Goodwill and Intangible Assets [Line Items]
Unamortizable Goodwill						1,592
Value Added Services [Member]
Goodwill and Intangible Assets [Line Items]
Unamortizable Goodwill						$ 1,202