Supplemental Financial Information (Schedule Of Consolidating Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011
Schedule Of Supplemental Financial Information [Line Items]
Cash and cash equivalents	$ 80,848	$ 48,028	$ 71,127	$ 54,117
Accounts receivable, net	114,541	89,473
Inventories	116,899	116,357
Other current assets	15,290	13,380
Total current assets	327,578	267,238
Property, plant, and equipment, net	130,877	151,613
Goodwill	341,445	359,863
Acquired intangibles	93,332	98,759
Other assets	6,202	6,201
Total assets	899,434	883,674
Accounts payable	81,158	69,060
Accrued expenses	46,528	47,432
Current maturities of long-term debt	417	1,093
Total current liabilities	128,103	117,585
Long-term debt	213,601	206,710
Deferred income taxes	56,334	57,068
Other non-current liabilities	33,615	25,489
Total shareholders' equity	467,781	476,822
Total liabilities and shareholders' equity	899,434	883,674
Gibraltar Industries, Inc. [Member]
Schedule Of Supplemental Financial Information [Line Items]
Intercompany balances	19,409	(16,349)
Other current assets	7,148	6,524
Total current assets	26,557	(9,825)
Other assets	3,066	2,259
Investment in subsidiaries	649,490	688,450
Total assets	679,113	680,884
Accrued expenses	1,332	1,360
Total current liabilities	1,332	1,360
Long-term debt	210,000	202,702
Total shareholders' equity	467,781	476,822
Total liabilities and shareholders' equity	679,113	680,884
Guarantor Subsidiaries [Member]
Schedule Of Supplemental Financial Information [Line Items]
Cash and cash equivalents	59,956	26,163	50,375	34,691
Accounts receivable, net	101,407	78,565
Intercompany balances	2,193	37,397
Inventories	108,597	107,137
Other current assets	7,171	5,815
Total current assets	279,324	255,077
Property, plant, and equipment, net	118,699	140,394
Goodwill	334,123	331,404
Acquired intangibles	87,365	90,311
Other assets	3,135	3,941
Investment in subsidiaries	33,342	56,716
Total assets	855,988	877,843
Accounts payable	74,144	61,841
Accrued expenses	42,443	43,843
Current maturities of long-term debt	417	1,093
Total current liabilities	117,004	106,777
Long-term debt	3,601	4,008
Deferred income taxes	52,940	53,639
Other non-current liabilities	32,953	24,969
Total shareholders' equity	649,490	688,450
Total liabilities and shareholders' equity	855,988	877,843
Non-Guarantor Subsidiaries [Member]
Schedule Of Supplemental Financial Information [Line Items]
Cash and cash equivalents	20,892	21,865	20,752	19,426
Accounts receivable, net	13,134	10,908
Intercompany balances	(21,602)	(21,048)
Inventories	8,302	9,220
Other current assets	971	1,041
Total current assets	21,697	21,986
Property, plant, and equipment, net	12,178	11,219
Goodwill	7,322	28,459
Acquired intangibles	5,967	8,448
Other assets	1	1
Total assets	47,165	70,113
Accounts payable	7,014	7,219
Accrued expenses	2,753	2,229
Total current liabilities	9,767	9,448
Deferred income taxes	3,394	3,429
Other non-current liabilities	662	520
Total shareholders' equity	33,342	56,716
Total liabilities and shareholders' equity	47,165	70,113
Eliminations [Member]
Schedule Of Supplemental Financial Information [Line Items]
Cash and cash equivalents
Investment in subsidiaries	(682,832)	(745,166)
Total assets	(682,832)	(745,166)
Total shareholders' equity	(682,832)	(745,166)
Total liabilities and shareholders' equity	$ (682,832)	$ (745,166)