Capital Structure - Components of Accumulated Other Comprehensive Loss (Parenthetical) (Detail) $ in Millions	6 Months Ended
Jun. 30, 2018 USD ($)
Equity [Abstract]
Unrealized losses on available-for-sale securities, tax benefit portion	$ 1
Defined benefit plans, Expense (income) reclassified into operations from other comprehensive income, Income tax benefit	3
Change in fair value of derivative instruments, change in fair value of derivative instruments, income taxes	$ 11

No definition available.

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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
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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

+ References

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