Supplemental Financial Information (Schedule Of Cash Flow, Supplemental Disclosures) (Details) (USD $)	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Net cash provided by (used in) operating activities of continuing operations	$ (2,531,000)	$ 11,995,000
Net cash (used in) provided by operating activities of discontinued operations	(3,134,000)	18,797,000
Net cash provided by (used in) operating activities	(5,665,000)	30,792,000
Cash paid for acquisitions, net of cash acquired	(107,605,000)
Purchases of property, plant, and equipment	(4,547,000)	(4,356,000)
Purchase of equity method investment	(250,000)	(750,000)
Net proceeds from sale of property and equipment	474,000	68,000
Net proceeds from sale of businesses	59,029,000	29,164,000
Net cash provided by (used in) investing activities of continuing operations	(52,899,000)	24,126,000
Net cash used in investing activities of discontinued operations		(458,000)
Net cash provided by (used in) investing activities	(52,899,000)	23,668,000
Proceeds from long-term debt	62,558,000	8,559,000
Long-term debt payments	(42,958,000)	(58,959,000)
Net proceeds from issuance of common stock	10,000	270,000
Purchase of treasury stock at market prices	(819,000)	(1,108,000)
Payment of deferred financing fees		(64,000)
Excess tax benefit from stock compensation		63,000
Net cash (used in) provided by financing activities	18,791,000	(51,239,000)
Net increase (decrease) in cash and cash equivalents	(39,773,000)	3,221,000
Cash and cash equivalents at beginning of year	60,866,000	23,596,000
Cash and cash equivalents at end of period	21,093,000	26,817,000
Gibraltar Industries, Inc. [Member]
Net cash provided by (used in) operating activities of continuing operations	(7,976,000)	(8,655,000)
Net cash (used in) provided by operating activities of discontinued operations
Net cash provided by (used in) operating activities	(7,976,000)	(8,655,000)
Cash paid for acquisitions, net of cash acquired
Purchases of property, plant, and equipment
Purchase of equity method investment
Net proceeds from sale of property and equipment
Net proceeds from sale of businesses
Net cash provided by (used in) investing activities
Proceeds from long-term debt
Long-term debt payments
Net proceeds from issuance of common stock	10,000	270,000
Intercompany financing	8,785,000	9,493,000
Purchase of treasury stock at market prices	(819,000)	(1,108,000)
Net cash (used in) provided by financing activities	7,976,000	8,655,000
Net increase (decrease) in cash and cash equivalents
Cash and cash equivalents at beginning of year
Cash and cash equivalents at end of period
Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities of continuing operations	1,820,000	19,894,000
Net cash (used in) provided by operating activities of discontinued operations	(3,182,000)	19,686,000
Net cash provided by (used in) operating activities	(1,362,000)	39,580,000
Cash paid for acquisitions, net of cash acquired	(107,605,000)
Purchases of property, plant, and equipment	(4,272,000)	(4,104,000)
Purchase of equity method investment	(250,000)	(750,000)
Net proceeds from sale of property and equipment	474,000	64,000
Net proceeds from sale of businesses	59,029,000	29,164,000
Net cash provided by (used in) investing activities of continuing operations		24,374,000
Net cash used in investing activities of discontinued operations		(458,000)
Net cash provided by (used in) investing activities	(52,624,000)	23,916,000
Proceeds from long-term debt	62,558,000	8,559,000
Long-term debt payments	(42,958,000)	(58,959,000)
Intercompany financing	(8,651,000)	(8,814,000)
Payment of deferred financing fees		(64,000)
Excess tax benefit from stock compensation		63,000
Net cash (used in) provided by financing activities	10,949,000	(59,215,000)
Net increase (decrease) in cash and cash equivalents	(43,037,000)	4,281,000
Cash and cash equivalents at beginning of year	46,349,000	10,105,000
Cash and cash equivalents at end of period	3,312,000	14,386,000
Non-Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities of continuing operations	3,625,000	756,000
Net cash (used in) provided by operating activities of discontinued operations	48,000	(889,000)
Net cash provided by (used in) operating activities	3,673,000	(133,000)
Purchases of property, plant, and equipment	(275,000)	(252,000)
Net proceeds from sale of property and equipment		4,000
Net cash provided by (used in) investing activities of continuing operations		(248,000)
Net cash provided by (used in) investing activities	(275,000)	(248,000)
Intercompany financing	(134,000)	(679,000)
Net cash (used in) provided by financing activities	(134,000)	(679,000)
Net increase (decrease) in cash and cash equivalents	3,264,000	(1,060,000)
Cash and cash equivalents at beginning of year	14,517,000	13,491,000
Cash and cash equivalents at end of period	17,781,000	12,431,000
Eliminations [Member]
Net cash provided by (used in) operating activities of continuing operations
Net cash (used in) provided by operating activities of discontinued operations
Net cash provided by (used in) operating activities
Cash paid for acquisitions, net of cash acquired
Purchases of property, plant, and equipment
Purchase of equity method investment
Net proceeds from sale of property and equipment
Net proceeds from sale of businesses
Net cash provided by (used in) investing activities
Proceeds from long-term debt
Long-term debt payments
Net proceeds from issuance of common stock
Intercompany financing
Purchase of treasury stock at market prices
Net cash (used in) provided by financing activities
Net increase (decrease) in cash and cash equivalents
Cash and cash equivalents at beginning of year
Cash and cash equivalents at end of period