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Supplemental Financial Information (Schedule of Consolidating Statements of Operations) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 9 Months Ended
--- | --- | --- | ---
Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Sep. 30, 2015 | Jun. 30, 2016 | Sep. 30, 2016 | Sep. 30, 2015
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |  |  |  |
Net Sales | $ 272,734 | $ 265,738 | $ 237,671 | $ 304,994 | $ 503,409 | $ 776,143 | $ 758,780
Cost of sales | 204,847 |  |  | 243,598 |  | 585,263 | 623,350
Gross profit | 67,887 | 68,843 | 54,150 | 61,396 | 122,993 | 190,880 | 135,430
Selling, general, and administrative expense | 41,524 |  |  | 38,002 |  | 118,500 | 91,865
Income from operations | 26,363 | 28,416 | 17,601 | 23,394 | 46,017 | 72,380 | 43,565
Interest expense | 3,625 |  |  | 3,878 |  | 10,982 | 11,389
Other (income) expense | 0 |  |  | (1,780) |  | 7,840 | (4,238)
Income before taxes | 22,738 |  |  | 21,296 |  | 53,558 | 36,414
Provision for income taxes | 8,952 | (1,897) | 5,076 | 7,664 | 3,179 | 12,131 | 13,158
Income from continuing operations | 13,786 | 16,715 | 14,105 | 13,632 | 30,820 | 41,427 | 23,256
Loss before taxes | 0 |  |  | 0 |  | 0 | (44)
Benefit of income taxes | 0 |  |  | 0 |  | 0 | (16)
Loss from discontinued operations | 0 |  |  | 0 |  | 0 | (28)
Equity in earnings from subsidiaries | 0 |  |  | 0 |  | 0 | 0
Net income | 13,786 | $ 18,612 | $ 9,029 | 13,632 | $ 27,641 | 41,427 | 23,228
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 | 94 |  |  | 30 |  | 14,268 | 101
Income from operations | (94) |  |  | (30) |  | (14,268) | (101)
Interest expense | 3,403 |  |  | 3,403 |  | 10,207 | 10,207
Other (income) expense | 230 |  |  | 16 |  | 8,717 | 4
Income before taxes | (3,727) |  |  | (3,449) |  | (33,192) | (10,312)
Provision for income taxes | (1,416) |  |  | (1,210) |  | (10,898) | (3,617)
Income from continuing operations | (2,311) |  |  | (2,239) |  | (22,294) | (6,695)
Loss before taxes |  |  |  |  |  |  | 0
Benefit of income taxes |  |  |  |  |  |  | 0
Loss from discontinued operations |  |  |  |  |  |  | 0
Equity in earnings from subsidiaries | 15,746 |  |  | 17,742 |  | 64,006 | 32,248
Net income | 13,435 |  |  | 15,503 |  | 41,712 | 25,553
Reportable Legal Entities | Guarantor Subsidiaries |  |  |  |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |  |  |  |
Net Sales | 265,657 |  |  | 280,828 |  | 728,782 | 700,646
Cost of sales | 202,199 |  |  | 223,694 |  | 551,195 | 574,112
Gross profit | 63,458 |  |  | 57,134 |  | 177,587 | 126,534
Selling, general, and administrative expense | 38,664 |  |  | 33,392 |  | 100,101 | 83,076
Income from operations | 24,794 |  |  | 23,742 |  | 77,486 | 43,458
Interest expense | 241 |  |  | 494 |  | 836 | 1,254
Other (income) expense | (135) |  |  | (1,597) |  | (14) | (4,062)
Income before taxes | 24,688 |  |  | 24,845 |  | 76,664 | 46,266
Provision for income taxes | 10,804 |  |  | 8,514 |  | 22,189 | 15,949
Income from continuing operations | 13,884 |  |  | 16,331 |  | 54,475 | 30,317
Loss before taxes |  |  |  |  |  |  | (44)
Benefit of income taxes |  |  |  |  |  |  | (16)
Loss from discontinued operations |  |  |  |  |  |  | (28)
Equity in earnings from subsidiaries | 1,862 |  |  | 1,411 |  | 9,531 | 1,959
Net income | 15,746 |  |  | 17,742 |  | 64,006 | 32,248
Reportable Legal Entities | Non-Guarantor Subsidiaries |  |  |  |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |  |  |  |
Net Sales | 15,799 |  |  | 34,565 |  | 63,014 | 76,732
Cost of sales | 11,721 |  |  | 28,432 |  | 49,436 | 65,511
Gross profit | 4,078 |  |  | 6,133 |  | 13,578 | 11,221
Selling, general, and administrative expense | 2,766 |  |  | 4,580 |  | 4,131 | 8,688
Income from operations | 1,312 |  |  | 1,553 |  | 9,447 | 2,533
Interest expense | (19) |  |  | (19) |  | (61) | (72)
Other (income) expense | (95) |  |  | (199) |  | (863) | (180)
Income before taxes | 1,426 |  |  | 1,771 |  | 10,371 | 2,785
Provision for income taxes | (436) |  |  | 360 |  | 840 | 826
Income from continuing operations | 1,862 |  |  | 1,411 |  | 9,531 | 1,959
Loss before taxes |  |  |  |  |  |  | 0
Benefit of income taxes |  |  |  |  |  |  | 0
Loss from discontinued operations |  |  |  |  |  |  | 0
Equity in earnings from subsidiaries | 0 |  |  | 0 |  | 0 | 0
Net income | 1,862 |  |  | 1,411 |  | 9,531 | 1,959
Eliminations |  |  |  |  |  |  |
Schedule Of Supplemental Financial Information [Line Items] |  |  |  |  |  |  |
Net Sales | (8,722) |  |  | (10,399) |  | (15,653) | (18,598)
Cost of sales | (9,073) |  |  | (8,528) |  | (15,368) | (16,273)
Gross profit | 351 |  |  | (1,871) |  | (285) | (2,325)
Selling, general, and administrative expense | 0 |  |  | 0 |  | 0 | 0
Income from operations | 351 |  |  | (1,871) |  | (285) | (2,325)
Interest expense | 0 |  |  | 0 |  | 0 | 0
Other (income) expense | 0 |  |  | 0 |  | 0 | 0
Income before taxes | 351 |  |  | (1,871) |  | (285) | (2,325)
Provision for income taxes | 0 |  |  | 0 |  | 0 | 0
Income from continuing operations | 351 |  |  | (1,871) |  | (285) | (2,325)
Loss before taxes |  |  |  |  |  |  | 0
Benefit of income taxes |  |  |  |  |  |  | 0
Loss from discontinued operations |  |  |  |  |  |  | 0
Equity in earnings from subsidiaries | (17,608) |  |  | (19,153) |  | (73,537) | (34,207)
Net income | $ (17,257) |  |  | $ (21,024) |  | $ (73,822) | $ (36,532)

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- Definition The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.4) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=68048583&loc=d3e3636-108311 + Details
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