Guarantor and Non-guarantor Financial Statements, Condensed Consolidated Statements of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Net sales	$ 163,428	$ 184,007	$ 532,467	$ 532,366
Cost of goods sold	145,165	164,095	467,367	473,009
Gross profit	18,263	19,912	65,100	59,357
Operating expenses	10,765	9,868	34,090	30,440
Income from operations	7,498	10,044	31,010	28,917
Other income (expense):
Interest expense, net	(8,249)	(8,444)	(24,953)	(25,351)
Equity in earnings of subsidiaries	0	0	0	0
Other expense, net	(1,142)	(805)	(2,398)	(1,504)
Income (loss) before income taxes from continuing operations	(1,893)	795	3,659	2,062
Income tax provision (benefit)	(3,671)	(410)	(3,663)	(967)
Net income from continuing operations	1,778	1,205	7,322	3,029
Discontinued operations, net of tax	42	(106)	249	(208)
Net income	1,820	1,099	7,571	2,821
Comprehensive income	(1,439)	1,571	23,152	3,766
Eliminations [Member]
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Net sales	(57,322)	(56,112)	(175,462)	(156,485)
Cost of goods sold	(56,974)	(55,701)	(174,405)	(155,143)
Gross profit	(348)	(411)	(1,057)	(1,342)
Operating expenses	0	0	0	0
Income from operations	(348)	(411)	(1,057)	(1,342)
Other income (expense):
Interest expense, net	0	0	0	0
Equity in earnings of subsidiaries	(10,038)	(5,385)	(31,950)	(19,446)
Other expense, net	0	0	0	0
Income (loss) before income taxes from continuing operations	(10,386)	(5,796)	(33,007)	(20,788)
Income tax provision (benefit)	0	0	0	0
Net income from continuing operations	(10,386)	(5,796)	(33,007)	(20,788)
Discontinued operations, net of tax	0	0	0	0
Net income	(10,386)	(5,796)	(33,007)	(20,788)
Comprehensive income	(7,601)	(6,251)	(48,528)	(21,694)
Parent [Member]
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Net sales	123,912	124,025	379,041	355,600
Cost of goods sold	117,925	111,184	348,803	318,350
Gross profit	5,987	12,841	30,238	37,250
Operating expenses	10,363	9,623	33,100	29,588
Income from operations	(4,376)	3,218	(2,862)	7,662
Other income (expense):
Interest expense, net	(8,749)	(8,695)	(26,191)	(26,118)
Equity in earnings of subsidiaries	10,038	5,385	31,950	19,446
Other expense, net	(384)	(714)	(663)	(1,591)
Income (loss) before income taxes from continuing operations	(3,471)	(806)	2,234	(601)
Income tax provision (benefit)	(5,291)	(1,905)	(5,337)	(3,422)
Net income from continuing operations	1,820	1,099	7,571	2,821
Discontinued operations, net of tax	0	0	0	0
Net income	1,820	1,099	7,571	2,821
Comprehensive income	(1,439)	1,571	23,152	3,766
Guarantor Subsidiaries [Member]
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Net sales	66,262	82,505	234,426	233,339
Cost of goods sold	58,200	77,396	208,191	217,082
Gross profit	8,062	5,109	26,235	16,257
Operating expenses	369	204	873	706
Income from operations	7,693	4,905	25,362	15,551
Other income (expense):
Interest expense, net	(47)	(53)	(152)	(173)
Equity in earnings of subsidiaries	0	0	0	0
Other expense, net	0	327	0	453
Income (loss) before income taxes from continuing operations	7,646	5,179	25,210	15,831
Income tax provision (benefit)	925	925	578	1,068
Net income from continuing operations	6,721	4,254	24,632	14,763
Discontinued operations, net of tax	0	0	0	0
Net income	6,721	4,254	24,632	14,763
Comprehensive income	2,866	4,252	37,765	14,738
Non-guarantor Subsidiaries [Member]
CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS
Net sales	30,576	33,589	94,462	99,912
Cost of goods sold	26,014	31,216	84,778	92,720
Gross profit	4,562	2,373	9,684	7,192
Operating expenses	33	41	117	146
Income from operations	4,529	2,332	9,567	7,046
Other income (expense):
Interest expense, net	547	304	1,390	940
Equity in earnings of subsidiaries	0	0	0	0
Other expense, net	(758)	(418)	(1,735)	(366)
Income (loss) before income taxes from continuing operations	4,318	2,218	9,222	7,620
Income tax provision (benefit)	695	570	1,096	1,387
Net income from continuing operations	3,623	1,648	8,126	6,233
Discontinued operations, net of tax	42	(106)	249	(208)
Net income	3,665	1,542	8,375	6,025
Comprehensive income	$ 4,735	$ 1,999	$ 10,763	$ 6,956