Restructuring Charges (Tables)

12 Months Ended

Dec. 31, 2017

Restructuring and Related Activities [Abstract]

Roll Forward of Accrued Restructuring Expense

A roll-forward of the remaining accrued restructuring expense is as follows:

(Dollars in thousands)	Severance expenses			Write-downs and retirements of fixed assets			Lease cancellations			Total
Accrued at January 1, 2017	$	901		$	228		$	81		$	1,210
Payments	(901		)	—			(58		)	(959		)
Non-cash settlement	—			(228		)	—			(228		)
Accrued at December 31, 2017	$	—		$	—		$	23		$	23