Supplemental Financial Information (Schedule Of Consolidating Statements Of Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Schedule Of Supplemental Financial Information [Line Items]
Net income	$ 6,431	$ 7,732	$ 4,345	$ 4,085
Other comprehensive (loss) income:
Foreign currency translation adjustment	1,542	(804)	638	(3,901)
Change in unrealized loss on cash flow hedges, net of tax	(956)	0	(956)	0
Adjustment to retirement benefit liability, net of tax	2	2	4	4
Adjustment to post-retirement health care liability, net of tax	18	0	37	38
Other comprehensive income (loss)	606	(802)	(277)	(3,859)
Total comprehensive income	7,037	6,930	4,068	226
Gibraltar Industries, Inc.
Schedule Of Supplemental Financial Information [Line Items]
Net income	6,784	8,256	4,879	4,819
Other comprehensive (loss) income:
Foreign currency translation adjustment	0	0	0	0
Change in unrealized loss on cash flow hedges, net of tax	0		0
Adjustment to retirement benefit liability, net of tax	0	0	0	0
Adjustment to post-retirement health care liability, net of tax	0	0	0	0
Other comprehensive income (loss)	0	0	0	0
Total comprehensive income	6,784	8,256	4,879	4,819
Guarantor Subsidiaries
Schedule Of Supplemental Financial Information [Line Items]
Net income	9,025	10,457	9,340	13,864
Other comprehensive (loss) income:
Foreign currency translation adjustment	0	0	0	0
Change in unrealized loss on cash flow hedges, net of tax	(956)		(956)
Adjustment to retirement benefit liability, net of tax	2	2	4	4
Adjustment to post-retirement health care liability, net of tax	18	0	37	38
Other comprehensive income (loss)	(936)	2	(915)	42
Total comprehensive income	8,089	10,459	8,425	13,906
Non-Guarantor Subsidiaries
Schedule Of Supplemental Financial Information [Line Items]
Net income	794	413	1,362	1,051
Other comprehensive (loss) income:
Foreign currency translation adjustment	1,542	(804)	638	(3,901)
Change in unrealized loss on cash flow hedges, net of tax	0		0
Adjustment to retirement benefit liability, net of tax	0	0	0	0
Adjustment to post-retirement health care liability, net of tax	0	0	0	0
Other comprehensive income (loss)	1,542	(804)	638	(3,901)
Total comprehensive income	2,336	(391)	2,000	(2,850)
Eliminations
Schedule Of Supplemental Financial Information [Line Items]
Net income	(10,172)	(11,394)	(11,236)	(15,649)
Other comprehensive (loss) income:
Foreign currency translation adjustment	0	0	0	0
Change in unrealized loss on cash flow hedges, net of tax	0		0
Adjustment to retirement benefit liability, net of tax	0	0	0	0
Adjustment to post-retirement health care liability, net of tax	0	0	0	0
Other comprehensive income (loss)	0	0	0	0
Total comprehensive income	$ (10,172)	$ (11,394)	$ (11,236)	$ (15,649)