Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Capital Leases - Future Minimum Lease Payments
2016	$ 5,174
2017	3,051
2018	789
2019	477
2020	40
Total minimum lease payments	9,531
Less amount representing interest	740
Present value of future minimum lease payments	8,791
Less current installments of obligations under capital leases	4,626	$ 4,373
Long-term capital lease obligations	4,165	6,779
Operating Leases - Future Minimum Lease Payments
2016	3,214
2017	2,445
2018	1,310
2019	1,129
2020	654
Thereafter	41
Total minimum lease payments	8,793
Operating Leases - additional information
Rent expense	3,200	3,400	$ 3,300
Capital Leases - additional information
Amortization expense	$ 4,600	$ 2,300	$ 1,900