Supplemental Financial Information (Schedule Of Condensed Consolidating Statements Of Cash Flows) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash Flows from Operating Activities
Net cash provided by (used in) operating activities of continuing operations	$ (13,049,000)	$ (9,424,000)
Net cash (used in) provided by operating activities of discontinued operations	(31,000)	(3,086,000)
Net cash provided by (used in) operating activities	(13,080,000)	(12,510,000)
Cash paid for acquisitions, net of cash received	(2,705,000)
Net proceeds from sale of businesses		58,000,000
Net proceeds from sale of property and equipment	8,000	463,000
Purchase of other investments		(250,000)
Purchases of property, plant, and equipment	(2,743,000)	(1,785,000)
Net cash used in investing activities	(5,440,000)	56,428,000
Long-term debt payments	(2,000)
Purchase of treasury stock at market prices	(888,000)	(730,000)
Excess tax benefit from stock compensation	98,000
Net proceeds from issuance of common stock		10,000
Net cash (used in) provided by financing activities	(792,000)	(720,000)
Effect of exchange rate changes on cash	522,000	440,000
Net (decrease) increase in cash and cash equivalents	(18,790,000)	43,638,000
Cash and cash equivalents at beginning of year	54,117,000	60,866,000
Cash and cash equivalents at end of period	35,327,000	104,504,000
Gibraltar Industries, Inc. [Member]
Cash Flows from Operating Activities
Net cash provided by (used in) operating activities of continuing operations	148,000	130,000
Net cash provided by (used in) operating activities	148,000	130,000
Purchase of treasury stock at market prices	(888,000)	(730,000)
Intercompany financing	642,000	590,000
Excess tax benefit from stock compensation	98,000
Net proceeds from issuance of common stock		10,000
Net cash (used in) provided by financing activities	(148,000)	(130,000)
Guarantor Subsidiaries [Member]
Cash Flows from Operating Activities
Net cash provided by (used in) operating activities of continuing operations	(13,582,000)	(11,610,000)
Net cash (used in) provided by operating activities of discontinued operations	(31,000)	(3,134,000)
Net cash provided by (used in) operating activities	(13,613,000)	(14,744,000)
Net proceeds from sale of businesses		58,000,000
Net proceeds from sale of property and equipment	8,000	463,000
Purchase of other investments		(250,000)
Purchases of property, plant, and equipment	(2,315,000)	(1,654,000)
Net cash used in investing activities	(2,307,000)	56,559,000
Long-term debt payments	(2,000)
Intercompany financing	(278,000)	(2,281,000)
Net cash (used in) provided by financing activities	(280,000)	(2,281,000)
Net (decrease) increase in cash and cash equivalents	(16,200,000)	39,534,000
Cash and cash equivalents at beginning of year	34,691,000	46,349,000
Cash and cash equivalents at end of period	18,491,000	85,883,000
Non-Guarantor Subsidiaries [Member]
Cash Flows from Operating Activities
Net cash provided by (used in) operating activities of continuing operations	385,000	2,056,000
Net cash (used in) provided by operating activities of discontinued operations		48,000
Net cash provided by (used in) operating activities	385,000	2,104,000
Cash paid for acquisitions, net of cash received	(2,705,000)
Purchases of property, plant, and equipment	(428,000)	(131,000)
Net cash used in investing activities	(3,133,000)	(131,000)
Intercompany financing	(364,000)	1,691,000
Net cash (used in) provided by financing activities	(364,000)	1,691,000
Effect of exchange rate changes on cash	522,000	440,000
Net (decrease) increase in cash and cash equivalents	(2,590,000)	4,104,000
Cash and cash equivalents at beginning of year	19,426,000	14,517,000
Cash and cash equivalents at end of period	16,836,000	18,621,000
Eliminations [Member]
Cash Flows from Operating Activities
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
Net proceeds from sale of businesses
Net proceeds from sale of property and equipment
Purchase of other investments
Purchases of property, plant, and equipment
Net cash used in investing activities
Purchase of treasury stock at market prices
Intercompany financing
Net proceeds from issuance of common stock
Net cash (used in) provided by financing activities
Effect of exchange rate changes on cash
Net (decrease) increase in cash and cash equivalents
Cash and cash equivalents at beginning of year
Cash and cash equivalents at end of period