Fair Value Measurements - Summary of Fair Value and Carrying Value of Financial Assets and Liabilities (Parenthetical) (Detail) - USD ($) |
12 Months Ended | |
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Dec. 31, 2016 |
Dec. 31, 2017 |
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| Fair Value Disclosures [Abstract] | ||
| Amortized cost | $ 61,000,000 | $ 153,000,000 |
| Receivables held for sale | $ 0 |
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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- Definition The amount of financing receivables reclassified to held for sale during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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