Schedule of Pre-Tax Income (Loss) Effects of Cash Flow Hedges (Detail) - Cash Flow Hedges - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	$ 995	$ 122
Gain (loss) reclassified into net income from OCI	47	44
Gain (loss) recognized in net income (loss)	0	2
Interest Rate Swaps Hedging Assets \| Net Investment Income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	1,041	137
Gain (loss) reclassified into net income from OCI	43	38
Gain (loss) recognized in net income (loss)	0	0
Interest Rate Swaps Hedging Assets \| Net Investment (Gains) Losses
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	0	0
Gain (loss) reclassified into net income from OCI	4	6
Gain (loss) recognized in net income (loss)	0	0
Interest Rate Swaps Hedging Liabilities \| Interest Expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	(63)	(12)
Gain (loss) reclassified into net income from OCI	0	0
Gain (loss) recognized in net income (loss)	0	0
Foreign currency swaps \| Net Investment Income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI	17	(3)
Gain (loss) reclassified into net income from OCI	0	0
Gain (loss) recognized in net income (loss)	$ 0	0
Foreign currency swaps \| Net Investment (Gains) Losses
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss) recognized in OCI		0
Gain (loss) reclassified into net income from OCI		0
Gain (loss) recognized in net income (loss)		$ 2

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- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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- Definition

The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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- Definition

Amount before tax of 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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