Contractual Maturities of Company's Corporate Debt (Detail) $ in Millions	Dec. 31, 2020 USD ($)
Long-Term Debt And Borrowing Arrangements [Abstract]
2016	$ 19
2017	18
2018	18
2019	732
2020	1,182
Thereafter	2,289
Total	$ 4,258

Amount of short-term and long-term debt and lease obligation.

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-SubTopic 210
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
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