Supplemental Financial Information (Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 68,858	$ 110,610	$ 97,039	$ 48,028
Accounts receivable, net of reserve	164,969	101,141
Intercompany balances	0	0
Inventories	107,058	128,743
Other current assets	10,537	19,937
Total current assets	351,422	360,431
Property, plant, and equipment, net	118,932	129,575
Goodwill	292,390	236,044	341,174
Acquired intangibles	123,013	82,215
Other assets	4,015	2,206
Investment in subsidiaries	0	0
Total assets	889,772	810,471	889,571
Current liabilities:
Accounts payable	89,204	81,246
Accrued expenses	67,605	52,439
Billings in Excess of Cost	28,186	0
Current maturities of long-term debt	400	400
Total current liabilities	185,395	134,085
Long-term debt	208,882	209,511
Deferred income taxes	42,654	49,772
Other non-current liabilities	42,755	29,874
Total shareholders’ equity	410,086	387,229	471,749	476,822
Total liabilities and shareholders' equity	889,772	810,471
Gibraltar Industries, Inc.
Current assets:
Cash and cash equivalents	0	0	0	0
Accounts receivable, net of reserve	0	0
Intercompany balances	15,023	21,619
Inventories	0	0
Other current assets	4,535	4,484
Total current assets	19,558	26,103
Property, plant, and equipment, net	0	0
Goodwill	0	0
Acquired intangibles	0	0
Other assets	0	0
Investment in subsidiaries	603,208	573,664
Total assets	622,766	599,767
Current liabilities:
Accounts payable	0	0
Accrued expenses	5,127	5,469
Billings in Excess of Cost	0
Current maturities of long-term debt	0	0
Total current liabilities	5,127	5,469
Long-term debt	207,553	207,069
Deferred income taxes	0	0
Other non-current liabilities	0	0
Total shareholders’ equity	410,086	387,229
Total liabilities and shareholders' equity	622,766	599,767
Guarantor Subsidiaries
Current assets:
Cash and cash equivalents	39,597	91,466	75,856	26,163
Accounts receivable, net of reserve	142,674	91,713
Intercompany balances	12,033	(1,850)
Inventories	99,132	120,091
Other current assets	2,957	14,488
Total current assets	296,393	315,908
Property, plant, and equipment, net	106,413	116,628
Goodwill	270,017	229,558
Acquired intangibles	111,734	77,259
Other assets	4,015	2,206
Investment in subsidiaries	54,792	32,404
Total assets	843,364	773,963
Current liabilities:
Accounts payable	81,551	74,751
Accrued expenses	55,363	45,561
Billings in Excess of Cost	20,548
Current maturities of long-term debt	400	400
Total current liabilities	157,862	120,712
Long-term debt	1,329	2,442
Deferred income taxes	38,763	47,717
Other non-current liabilities	42,202	29,428
Total shareholders’ equity	603,208	573,664
Total liabilities and shareholders' equity	843,364	773,963
Non-Guarantor Subsidiaries
Current assets:
Cash and cash equivalents	29,261	19,144	21,183	21,865
Accounts receivable, net of reserve	22,295	9,428
Intercompany balances	(27,056)	(19,769)
Inventories	7,926	8,652
Other current assets	3,045	965
Total current assets	35,471	18,420
Property, plant, and equipment, net	12,519	12,947
Goodwill	22,373	6,486
Acquired intangibles	11,279	4,956
Other assets	0	0
Investment in subsidiaries	0	0
Total assets	81,642	42,809
Current liabilities:
Accounts payable	7,653	6,495
Accrued expenses	7,115	1,409
Billings in Excess of Cost	7,638
Current maturities of long-term debt	0	0
Total current liabilities	22,406	7,904
Long-term debt	0	0
Deferred income taxes	3,891	2,055
Other non-current liabilities	553	446
Total shareholders’ equity	54,792	32,404
Total liabilities and shareholders' equity	81,642	42,809
Eliminations
Current assets:
Cash and cash equivalents	0	0	$ 0	$ 0
Accounts receivable, net of reserve	0	0
Intercompany balances	0	0
Inventories	0	0
Other current assets	0	0
Total current assets	0	0
Property, plant, and equipment, net	0	0
Goodwill	0	0
Acquired intangibles	0	0
Other assets	0	0
Investment in subsidiaries	(658,000)	(606,068)
Total assets	(658,000)	(606,068)
Current liabilities:
Accounts payable	0	0
Accrued expenses	0	0
Billings in Excess of Cost	0
Current maturities of long-term debt	0	0
Total current liabilities	0	0
Long-term debt	0	0
Deferred income taxes	0	0
Other non-current liabilities	0	0
Total shareholders’ equity	(658,000)	(606,068)
Total liabilities and shareholders' equity	$ (658,000)	$ (606,068)