Accounts Receivable (Tables)

3 Months Ended

Mar. 31, 2018

Accounts Receivable, Net [Abstract]

Schedule of Accounts, Notes, Loans and Financing Receivable

Accounts receivable consisted of the following as of March 31, 2018 and December 31, 2017 (dollars in thousands):

	March 31, 2018			December 31, 2017
Accounts receivable – trade	$	400,926		$	401,723
Accounts receivable – grants from outside parties	16,142			17,734
Accounts receivable – insurance and other third-party claims	20,015			10,753
Total accounts receivable	437,083			430,210
Less: Allowance for doubtful accounts	(14,356		)	(13,505		)
Accounts receivable, net	$	422,727		$	416,705

Grant amortization offset to depreciation expense

The following table sets forth the offset to depreciation expense from the amortization of deferred grants recorded by the Company during the three months ended March 31, 2018 and 2017 (dollars in thousands):

	Three Months Ended
	March 31,
	2018		2017
Amortization of deferred grants	$	2,467	$	3,245