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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Mar. 31, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Effective income tax rate | 35.10% |  | 6.50% | 8.70% | 6.60%
Income Tax Benefit Offset Amount From Cares Act 2020 Aid | $ 100 | $ 123 |  |  |
Net operating losses carried back term due to cares act |  |  |  | 5 years |
Refund claim to carryback net operating loss from Settlement with Taxing Authority | 94 |  |  | $ 94 |
Favorably impacted by an income tax benefit | 90 |  |  | 90 |
Income tax receivable recorded in other assets | 90 |  |  | 90 |
Tax Year 2014 [Member] |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |
Refund claim to carryback net operating loss from Settlement with Taxing Authority | $ 90 |  |  | $ 90 |

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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