Share Repurchase Transactions and Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss (Parenthetical) (Detail) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Equity [Abstract]
Unrealized gains (losses) on available-for-sale securities, tax benefit	$ 2
Foreign currency translation adjustments, income tax expense	1
Defined benefit plans, Expense reclassified into operations from other comprehensive income, Income tax benefits	2
Change in fair value of derivative instruments, Expense reclassified into operations from other comprehensive income, Income tax benefits	$ 2

Other comprehensive income unrealized holding loss on securities arising during period tax benefit.

No definition available.

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- Definition

Other comprehensive loss foreign currency translation adjustment tax expense.

+ References

No definition available.

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- References

No definition available.

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- Definition

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

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- Definition

Amount of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4569616-111683

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580

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