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Supplemental Financial Information (Schedule of Consolidating Statements of Operations) (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Schedule Of Supplemental Financial Information [Line Items] |  |
Net Sales | $ 215,337 | $ 206,605
Cost of sales | 167,019 | 157,350
Gross profit | 48,318 | 49,255
Selling, general, and administrative expense | 34,475 | 39,576
Income from operations | 13,843 | 9,679
Interest expense | 3,269 | 3,576
Other (income) expense | (585) | 54
Income before taxes | 11,159 | 6,049
Provision for income taxes | 2,807 | 2,053
Income from continuing operations | 8,352 | 3,996
Equity in earnings from subsidiaries | 0 | 0
Net income | 8,352 | 3,996
Reportable Legal Entities | Guarantor Subsidiaries |  |
Schedule Of Supplemental Financial Information [Line Items] |  |
Net Sales | 204,467 | 197,748
Cost of sales | 158,584 | 150,507
Gross profit | 45,883 | 47,241
Selling, general, and administrative expense | 32,724 | 36,506
Income from operations | 13,159 | 10,735
Interest expense | (84) | 192
Other (income) expense | 28 | 130
Income before taxes | 13,215 | 10,413
Provision for income taxes | 3,335 | 3,378
Equity in earnings from subsidiaries | 1,090 | (692)
Net income | 10,970 | 6,343
Reportable Legal Entities | Non-Guarantor Subsidiaries |  |
Schedule Of Supplemental Financial Information [Line Items] |  |
Net Sales | 12,330 | 11,242
Cost of sales | 9,758 | 8,982
Gross profit | 2,572 | 2,260
Selling, general, and administrative expense | 1,707 | 3,027
Income from operations | 865 | (767)
Interest expense | (49) | (18)
Other (income) expense | (613) | (76)
Income before taxes | 1,527 | (673)
Provision for income taxes | 437 | 19
Equity in earnings from subsidiaries | 0 | 0
Net income | 1,090 | (692)
Reportable Legal Entities | Gibraltar Industries, Inc. |  |
Schedule Of Supplemental Financial Information [Line Items] |  |
Net Sales | 0 | 0
Cost of sales | 0 | 0
Gross profit | 0 | 0
Selling, general, and administrative expense | 44 | 43
Income from operations | (44) | (43)
Interest expense | 3,402 | 3,402
Other (income) expense | 0 | 0
Income before taxes | (3,446) | (3,445)
Provision for income taxes | (965) | (1,344)
Equity in earnings from subsidiaries | 10,970 | 6,343
Net income | 8,489 | 4,242
Eliminations |  |
Schedule Of Supplemental Financial Information [Line Items] |  |
Net Sales | (1,460) | (2,385)
Cost of sales | (1,323) | (2,139)
Gross profit | (137) | (246)
Selling, general, and administrative expense | 0 | 0
Income from operations | (137) | (246)
Interest expense | 0 | 0
Other (income) expense | 0 | 0
Income before taxes | (137) | (246)
Provision for income taxes | 0 | 0
Equity in earnings from subsidiaries | (12,060) | (5,651)
Net income | $ (12,197) | $ (5,897)

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