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Supplemental Financial Information (Schedule of Consolidating Statements of Operations) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | $ 274,574 | $ 272,734 | $ 728,806 | $ 776,143
Cost of sales | 205,839 | 204,847 | 548,991 | 585,263
Gross profit | 68,735 | 67,887 | 179,815 | 190,880
Selling, general, and administrative expense | 33,042 | 41,365 | 109,513 | 118,021
Income from operations | 35,693 | 26,522 | 70,302 | 72,859
Interest expense | 3,486 | 3,625 | 10,612 | 10,982
Other expense | 404 | 159 | 811 | 8,319
Income before taxes | 31,803 | 22,738 | 58,879 | 53,558
Provision for income taxes | 11,184 | 8,952 | 21,090 | 12,131
Income from continuing operations | 20,619 | 13,786 | 37,789 | 41,427
Loss from discontinued operations before taxes | 0 | 0 | (644) | 0
Benefit of income taxes | 0 | 0 | (239) | 0
Loss from discontinued operations | 0 | 0 | (405) | 0
Equity in earnings from subsidiaries | 0 | 0 | 0 | 0
Net income | 20,619 | 13,786 | 37,384 | 41,427
Reportable Legal Entities | Guarantor Subsidiaries |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | 264,448 | 265,657 | 700,848 | 728,782
Cost of sales | 198,103 | 202,199 | 527,389 | 551,195
Gross profit | 66,345 | 63,458 | 173,459 | 177,587
Selling, general, and administrative expense | 31,003 | 38,505 | 101,190 | 99,622
Income from operations | 35,342 | 24,953 | 72,269 | 77,965
Interest expense | 105 | 241 | 459 | 836
Other expense | 100 | 24 | 345 | 465
Income before taxes | 35,137 | 24,688 | 71,465 | 76,664
Provision for income taxes | 12,219 | 10,804 | 24,957 | 22,189
Income from continuing operations |  |  | 46,508 |
Loss from discontinued operations before taxes |  |  | (644) |
Benefit of income taxes |  |  | (239) |
Loss from discontinued operations |  |  | (405) |
Equity in earnings from subsidiaries | 293 | 1,862 | (1,747) | 9,531
Net income | 23,211 | 15,746 | 44,356 | 64,006
Reportable Legal Entities | Non-Guarantor Subsidiaries |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | 15,514 | 15,799 | 37,383 | 63,014
Cost of sales | 12,844 | 11,721 | 30,565 | 49,436
Gross profit | 2,670 | 4,078 | 6,818 | 13,578
Selling, general, and administrative expense | 2,005 | 2,766 | 8,212 | 4,131
Income from operations | 665 | 1,312 | (1,394) | 9,447
Interest expense | (21) | (19) | (54) | (61)
Other expense | 304 | (95) | 466 | (863)
Income before taxes | 382 | 1,426 | (1,806) | 10,371
Provision for income taxes | 89 | (436) | (59) | 840
Income from continuing operations |  |  | (1,747) |
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 | 293 | 1,862 | (1,747) | 9,531
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 | 94 | 111 | 14,268
Income from operations | (34) | (94) | (111) | (14,268)
Interest expense | 3,402 | 3,403 | 10,207 | 10,207
Other expense | 0 | 230 | 0 | 8,717
Income before taxes | (3,436) | (3,727) | (10,318) | (33,192)
Provision for income taxes | (1,124) | (1,416) | (3,808) | (10,898)
Income from continuing operations |  |  | (6,510) |
Loss from discontinued operations before taxes |  |  | 0 |
Benefit of income taxes |  |  | 0 |
Loss from discontinued operations |  |  | 0 |
Equity in earnings from subsidiaries | 23,211 | 15,746 | 44,356 | 64,006
Net income | 20,899 | 13,435 | 37,846 | 41,712
Eliminations |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |
Net Sales | (5,388) | (8,722) | (9,425) | (15,653)
Cost of sales | (5,108) | (9,073) | (8,963) | (15,368)
Gross profit | (280) | 351 | (462) | (285)
Selling, general, and administrative expense | 0 | 0 | 0 | 0
Income from operations | (280) | 351 | (462) | (285)
Interest expense | 0 | 0 | 0 | 0
Other expense | 0 | 0 | 0 | 0
Income before taxes | (280) | 351 | (462) | (285)
Provision for income taxes | 0 | 0 | 0 | 0
Income from continuing operations |  |  | (462) |
Loss from discontinued operations before taxes |  |  | 0 |
Benefit of income taxes |  |  | 0 |
Loss from discontinued operations |  |  | 0 |
Equity in earnings from subsidiaries | (23,504) | (17,608) | (42,609) | (73,537)
Net income | $ (23,784) | $ (17,257) | $ (43,071) | $ (73,822)

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