Accounts Receivable Accounts Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	$ 375,993	$ 388,671
Allowance for doubtful accounts	(12,070)	(6,213)	$ (5,826)	$ (3,755)
Accounts receivable, net	363,923	382,458
Accounts receivable - trade [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	353,347	339,100
Accounts receivable - grants from outside parties [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	10,652	22,997
Accounts receivable - insurance and other third party claims [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	11,994	$ 26,574
GRail [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	12,000
P&W [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts receivable, net	$ 6,800