Supplemental Financial Information (Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 170,177	$ 68,858	$ 110,610	$ 97,039
Accounts receivable, net	124,072	164,969
Intercompany balances	0	0
Inventories	89,612	107,058
Other current assets	7,336	10,537
Total current assets	391,197	351,422
Property, plant, and equipment, net	108,304	118,932
Goodwill	304,032	292,390	236,044
Acquired intangibles	110,790	123,013
Other assets	3,922	4,015
Investment in subsidiaries	0	0
Total assets	918,245	889,772	810,471
Current liabilities:
Accounts payable	69,944	89,204
Accrued expenses	70,392	67,605
Billings in Excess of Cost	11,352	28,186
Current maturities of long-term debt	400	400
Total current liabilities	152,088	185,395
Long-term debt	209,237	208,882
Deferred income taxes	38,002	42,654
Other non-current liabilities	58,038	42,755
Total shareholders’ equity	460,880	410,086	387,229	471,749
Total liabilities and shareholders' equity	918,245	889,772
Gibraltar Industries, Inc.
Current assets:
Cash and cash equivalents	0	0	0	0
Accounts receivable, net	0	0
Intercompany balances	(615)	15,023
Inventories	0	0
Other current assets	13,783	4,535
Total current assets	13,168	19,558
Property, plant, and equipment, net	0	0
Goodwill	0	0
Acquired intangibles	0	0
Other assets	0	0
Investment in subsidiaries	663,118	603,208
Total assets	676,286	622,766
Current liabilities:
Accounts payable	0	0
Accrued expenses	7,369	5,127
Billings in Excess of Cost	0	0
Current maturities of long-term debt	0	0
Total current liabilities	7,369	5,127
Long-term debt	208,037	207,553
Deferred income taxes	0	0
Other non-current liabilities	0	0
Total shareholders’ equity	460,880	410,086
Total liabilities and shareholders' equity	676,286	622,766
Guarantor Subsidiaries
Current assets:
Cash and cash equivalents	143,826	39,597	91,466	75,856
Accounts receivable, net	117,526	142,674
Intercompany balances	6,152	12,033
Inventories	85,483	99,132
Other current assets	(10,070)	2,957
Total current assets	342,917	296,393
Property, plant, and equipment, net	104,642	106,413
Goodwill	282,300	270,017
Acquired intangibles	101,520	111,734
Other assets	3,922	4,015
Investment in subsidiaries	58,477	54,792
Total assets	893,778	843,364
Current liabilities:
Accounts payable	66,363	81,551
Accrued expenses	60,004	55,363
Billings in Excess of Cost	9,301	20,548
Current maturities of long-term debt	400	400
Total current liabilities	136,068	157,862
Long-term debt	1,200	1,329
Deferred income taxes	35,354	38,763
Other non-current liabilities	58,038	42,202
Total shareholders’ equity	663,118	603,208
Total liabilities and shareholders' equity	893,778	843,364
Non-Guarantor Subsidiaries
Current assets:
Cash and cash equivalents	26,351	29,261	19,144	21,183
Accounts receivable, net	6,546	22,295
Intercompany balances	(5,537)	(27,056)
Inventories	4,129	7,926
Other current assets	3,623	3,045
Total current assets	35,112	35,471
Property, plant, and equipment, net	3,662	12,519
Goodwill	21,732	22,373
Acquired intangibles	9,270	11,279
Other assets	0	0
Investment in subsidiaries	0	0
Total assets	69,776	81,642
Current liabilities:
Accounts payable	3,581	7,653
Accrued expenses	3,019	7,115
Billings in Excess of Cost	2,051	7,638
Current maturities of long-term debt	0	0
Total current liabilities	8,651	22,406
Long-term debt	0	0
Deferred income taxes	2,648	3,891
Other non-current liabilities	0	553
Total shareholders’ equity	58,477	54,792
Total liabilities and shareholders' equity	69,776	81,642
Eliminations
Current assets:
Cash and cash equivalents	0	0	$ 0	$ 0
Accounts receivable, net	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	(721,595)	(658,000)
Total assets	(721,595)	(658,000)
Current liabilities:
Accounts payable	0	0
Accrued expenses	0	0
Billings in Excess of Cost	0	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	(721,595)	(658,000)
Total liabilities and shareholders' equity	$ (721,595)	$ (658,000)