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Supplemental Financial Information (Schedule of Consolidating Statements of Operations) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | $ 247,627 | $ 265,738 | $ 454,232 | $ 503,409
Cost of sales | 185,802 | 196,895 | 343,152 | 380,416
Gross profit | 61,825 | 68,843 | 111,080 | 122,993
Selling, general, and administrative expense | 36,895 | 40,267 | 76,471 | 76,656
Income from operations | 24,930 | 28,576 | 34,609 | 46,337
Interest expense | 3,550 | 3,666 | 7,126 | 7,357
Other expense | 353 | 8,195 | 407 | 8,160
Income before taxes | 21,027 | 16,715 | 27,076 | 30,820
Provision for (benefit of) income taxes | 7,853 | (1,897) | 9,906 | 3,179
Income from continuing operations | 13,174 | 18,612 | 17,170 | 27,641
Loss from discontinued operations before taxes | (644) | 0 | (644) | 0
Benefit of income taxes | (239) | 0 | (239) | 0
Loss from discontinued operations | (405) | 0 | (405) | 0
Equity in earnings from subsidiaries | 0 | 0 | 0 | 0
Net income | 12,769 | 18,612 | 16,765 | 27,641
Guarantor Subsidiaries |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Loss from discontinued operations before taxes | (644) |  |  |
Benefit of income taxes | (239) |  |  |
Loss from discontinued operations | (405) |  |  |
Non-Guarantor Subsidiaries |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Loss from discontinued operations before taxes | 0 |  |  |
Benefit of income taxes | 0 |  |  |
Loss from discontinued operations | 0 |  |  |
Gibraltar Industries, Inc. |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Loss from discontinued operations before taxes | 0 |  |  |
Benefit of income taxes | 0 |  |  |
Loss from discontinued operations | 0 |  |  |
Reportable Legal Entities | Guarantor Subsidiaries |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | 238,652 | 247,912 | 436,400 | 463,125
Cost of sales | 178,779 | 183,557 | 329,286 | 348,996
Gross profit | 59,873 | 64,355 | 107,114 | 114,129
Selling, general, and administrative expense | 33,681 | 29,206 | 70,187 | 61,117
Income from operations | 26,192 | 35,149 | 36,927 | 53,012
Interest expense | 162 | 285 | 354 | 595
Other expense | 115 | 225 | 245 | 441
Income before taxes | 25,915 | 34,639 | 36,328 | 51,976
Provision for (benefit of) income taxes | 9,360 | 5,293 | 12,738 | 11,385
Income from continuing operations | 16,555 |  | 23,590 |
Loss from discontinued operations before taxes |  |  | (644) |
Benefit of income taxes |  |  | (239) |
Loss from discontinued operations |  |  | (405) |
Equity in earnings from subsidiaries | (1,348) | 7,418 | (2,040) | 7,669
Net income | 14,802 | 36,764 | 21,145 | 48,260
Reportable Legal Entities | Non-Guarantor Subsidiaries |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | 10,627 | 19,922 | 21,869 | 47,215
Cost of sales | 8,739 | 15,075 | 17,721 | 37,715
Gross profit | 1,888 | 4,847 | 4,148 | 9,500
Selling, general, and administrative expense | 3,180 | (3,073) | 6,207 | 1,365
Income from operations | (1,292) | 7,920 | (2,059) | 8,135
Interest expense | (15) | (20) | (33) | (42)
Other expense | 238 | (563) | 162 | (768)
Income before taxes | (1,515) | 8,503 | (2,188) | 8,945
Provision for (benefit of) income taxes | (167) | 1,085 | (148) | 1,276
Income from continuing operations | (1,348) |  | (2,040) |
Loss from discontinued operations before taxes |  |  | 0 |
Benefit of income taxes |  |  | 0 |
Loss from discontinued operations |  |  | 0 |
Equity in earnings from subsidiaries | 0 | 0 | 0 | 0
Net income | (1,348) | 7,418 | (2,040) | 7,669
Reportable Legal Entities | Gibraltar Industries, Inc. |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | 0 | 0 | 0 | 0
Cost of sales | 0 | 0 | 0 | 0
Gross profit | 0 | 0 | 0 | 0
Selling, general, and administrative expense | 34 | 14,134 | 77 | 14,174
Income from operations | (34) | (14,134) | (77) | (14,174)
Interest expense | 3,403 | 3,401 | 6,805 | 6,804
Other expense | 0 | 8,533 | 0 | 8,487
Income before taxes | (3,437) | (26,068) | (6,882) | (29,465)
Provision for (benefit of) income taxes | (1,340) | (8,275) | (2,684) | (9,482)
Income from continuing operations | (2,097) |  | (4,198) |
Loss from discontinued operations before taxes |  |  | 0 |
Benefit of income taxes |  |  | 0 |
Loss from discontinued operations |  |  | 0 |
Equity in earnings from subsidiaries | 14,802 | 36,764 | 21,145 | 48,260
Net income | 12,705 | 18,971 | 16,947 | 28,277
Eliminations |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | (1,652) | (2,096) | (4,037) | (6,931)
Cost of sales | (1,716) | (1,737) | (3,855) | (6,295)
Gross profit | 64 | (359) | (182) | (636)
Selling, general, and administrative expense | 0 | 0 | 0 | 0
Income from operations | 64 | (359) | (182) | (636)
Interest expense | 0 | 0 | 0 | 0
Other expense | 0 | 0 | 0 | 0
Income before taxes | 64 | (359) | (182) | (636)
Provision for (benefit of) income taxes | 0 | 0 | 0 | 0
Income from continuing operations | 64 |  | (182) |
Loss from discontinued operations before taxes | 0 |  | 0 |
Benefit of income taxes | 0 |  | 0 |
Loss from discontinued operations | 0 |  | 0 |
Equity in earnings from subsidiaries | (13,454) | (44,182) | (19,105) | (55,929)
Net income | $ (13,390) | $ (44,541) | $ (19,287) | $ (56,565)

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