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Income Taxes - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019
Income Tax Contingency [Line Items] |  |  |  |  |
Pretax income from continuing operations | $ 272,000 | $ 11,948,000 | $ 10,286,000 | $ 18,409,000 |
Income tax expense (benefit) | 2,553,000 | $ 5,655,000 | 5,161,000 | $ 7,513,000 |
Pension and restructuring charges |  |  | 7,800,000 |  |
Offsetting of income tax |  |  | 2,600,000 |  |
Decrease in valuation allowance |  |  | (3,400,000) |  |
Gross unrecognized tax benefits | 33,700,000 |  | 33,700,000 |  | $ 30,500,000
Unrecognized tax benefits that would impact effective tax rate | 22,900,000 |  | 22,900,000 |  |
Minimum [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Gross unrecognized tax benefits balance may decrease within the next twelve months | 0 |  | 0 |  |
Maximum [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Gross unrecognized tax benefits balance may decrease within the next twelve months | $ 1,200,000 |  | 1,200,000 |  |
Pension and Restructuring Charges [Member] |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Income tax expense (benefit) |  |  | $ 0 |  |

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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 20 -Section 25 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=68072869&loc=d3e41242-110953 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(10)) -URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(8)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-05(b)(2)) -URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884 Reference 9: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 31 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8924-108599 Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(15)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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