Property, Plant and Equipment - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Amortization expense on assets recorded under capital leases	$ 1,700	$ 1,700	$ 1,700
Accumulated depreciation and amortization, Capital lease assets	222,752	216,065
Related Party
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization, Capital lease assets	8,000	6,900
Non-Related Party
Property, Plant and Equipment [Line Items]
Accumulated depreciation and amortization, Capital lease assets	$ 6,300	$ 5,700