Balance Sheet Details (Tables)

12 Months Ended

Dec. 31, 2016

Balance Sheet Details [Abstract]

Schedule of Other Assets and Other Liabilities [Table Text Block]

The following table provides detail of selected balance sheet items:

December 31, (dollars in thousands)	2016		2015
Accounts receivable:
Trade receivables	$	82,851	$	91,324
Other receivables	2,262		3,055
Total accounts receivable, less allowances of $7,832 and $7,066	$	85,113	$	94,379
Inventories:
Finished goods	$	152,261	$	159,998
Work in process	1,625		1,183
Raw materials	4,432		4,944
Repair parts	10,558		10,763
Operating supplies	1,133		1,139
Total inventories, less loss provisions of $9,484 and $5,313	$	170,009	$	178,027
Accrued liabilities:
Accrued incentives	$	19,771	$	21,450
Other accrued liabilities	22,036		23,729
Total accrued liabilities	$	41,807	$	45,179