Commitments and Contingencies (Details) - USD ($)	3 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Outstanding purchase commitments	$ 27,200,000
Outstanding purchase commitments, equipment to be delivered in 2016	10,900,000
Outstanding purchase commitments, equipment to be delivered in 2017	9,200,000
Outstanding purchase commitments, equipment to be delivered in 2018	7,100,000
2016	409,000
2017	319,000
2018	125,000
2019	58,000
2020	0
Thereafter	0
Total future lease payments	911,000
Long-term Purchase Commitment [Line Items]
Property, plant and equipment, net	281,202,000	$ 283,378,000
Assets Held under Capital Leases
Long-term Purchase Commitment [Line Items]
Property, plant and equipment, net	900,000	$ 0
Accumulated depreciation	$ 100,000