Supplemental Financial Information (Schedule Of Consolidating Statements Of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Schedule Of Supplemental Financial Information [Line Items]
Net sales	$ 196,801	$ 192,171
Cost of sales	160,624	156,690
Gross profit	36,177	35,481
Selling, general, and administrative expense	30,981	28,458
(Loss) income from operations	5,196	7,023
Interest expense (income)	11,160	4,674
Other income	(66)	(31)
(Loss) income before taxes	(5,898)	2,380
(Benefit of) provision for income taxes	(2,255)	931
(Loss) income from continuing operations	(3,643)	1,449
Loss from discontinued operations before taxes	(7)	(137)
Benefit of income taxes	(3)	(50)
Loss from discontinued operations	(4)	(87)
Net (loss) income	(3,647)	1,362
Gibraltar Industries, Inc. [Member]
Schedule Of Supplemental Financial Information [Line Items]
Selling, general, and administrative expense	158	(30)
(Loss) income from operations	(158)	30
Interest expense (income)	10,883	4,235
(Loss) income before taxes	(11,041)	(4,205)
(Benefit of) provision for income taxes	(4,197)	(1,575)
(Loss) income from continuing operations	(6,844)	(2,630)
Equity in earnings from subsidiaries	3,407	4,350
Net (loss) income	(3,437)	1,720
Guarantor Subsidiaries [Member]
Schedule Of Supplemental Financial Information [Line Items]
Net sales	178,049	169,900
Cost of sales	144,395	137,798
Gross profit	33,654	32,102
Selling, general, and administrative expense	28,881	26,220
(Loss) income from operations	4,773	5,882
Interest expense (income)	308	472
Other income	(66)	(30)
(Loss) income before taxes	4,531	5,440
(Benefit of) provision for income taxes	1,758	2,098
(Loss) income from continuing operations	2,773	3,342
Loss from discontinued operations before taxes	(7)	(137)
Benefit of income taxes	(3)	(50)
Loss from discontinued operations	(4)	(87)
Equity in earnings from subsidiaries	638	1,095
Net (loss) income	3,407	4,350
Non-Guarantor Subsidiaries [Member]
Schedule Of Supplemental Financial Information [Line Items]
Net sales	23,217	27,614
Cost of sales	20,484	23,877
Gross profit	2,733	3,737
Selling, general, and administrative expense	1,942	2,268
(Loss) income from operations	791	1,469
Interest expense (income)	(31)	(33)
Other income		(1)
(Loss) income before taxes	822	1,503
(Benefit of) provision for income taxes	184	408
(Loss) income from continuing operations	638	1,095
Net (loss) income	638	1,095
Eliminations [Member]
Schedule Of Supplemental Financial Information [Line Items]
Net sales	(4,465)	(5,343)
Cost of sales	(4,255)	(4,985)
Gross profit	(210)	(358)
(Loss) income from operations	(210)	(358)
(Loss) income before taxes	(210)	(358)
(Loss) income from continuing operations	(210)	(358)
Equity in earnings from subsidiaries	(4,045)	(5,445)
Net (loss) income	$ (4,255)	$ (5,803)