Sensitivity analysis of decrease in fair value of derivatives impact of fifty basis point increase in interest rate.

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Sensitivity analysis of decrease in fair value of derivatives impact of twenty five basis point increase in interest rate.

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No definition available.

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Sensitivity analysis of increase in fair value of derivatives impact of fifty basis point decrease in interest rate.

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Sensitivity analysis of increase in fair value of derivatives impact of ten percent changes in assumed loan closing rates.

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No definition available.

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Sensitivity analysis of increase in fair value of derivatives impact of twenty five basis point decrease in interest rate.

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No definition available.

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Sensitivity analysis of increase in fair value of derivatives impact of twenty percent changes in assumed loan closing rates.

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No definition available.

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Increase in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
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Amount of loss from downward price adjustment on investment in equity security without readily determinable fair value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
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Amount of cumulative loss from downward price adjustment on investment in equity security without readily determinable fair value.

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Amount of gain from upward price adjustment on investment in equity security without readily determinable fair value.

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-Name Accounting Standards Codification
-Topic 321
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Amount of cumulative gain from upward price adjustment on investment in equity security without readily determinable fair value.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

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Amount of gain (loss) related to nonoperating activities, classified as other.

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The hypothetical financial impact of a 10 percent adverse change of the specified assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 50
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The hypothetical financial impact of a 20 percent adverse change of the specified assumption on the fair value of transferor's interests in transferred financial assets (including any servicing assets or servicing liabilities) as of the balance sheet date.

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Fair Value Measurements - Additional Information (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Net fair value of the interest rate lock commitments	$ 38,000,000
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 25 bps	21,000,000
Change in the fair value of the interest rate lock commitments, due to decrease in current interest rates of 50 bps	39,000,000
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 25 bps	22,000,000
Change in the fair value of the interest rate lock commitments, due to increase in current interest rates of 50 bps	45,000,000
Change in fair value of interest rate lock commitments, due to 10% adverse changes in the assumed loan closing rates	4,000,000
Change in fair value of interest rate lock commitments, due to 20% adverse changes in the assumed loan closing rates	7,000,000
Change in fair value of interest rate lock commitments, due to 10% favorable changes in the assumed loan closing rates	4,000,000
Change in fair value of interest rate lock commitments, due to 20% favorable changes in the assumed loan closing rates	7,000,000
Private equity, observable price change adjustment		$ 0
Private equity, cumulative observable price change	70,000,000
Private equity, impairment		9,000,000
Private equity, cumulative impairment	21,000,000
Fair value of embedded derivatives	58,000,000
Gain on embedded derivatives	9,000,000
Residential Mortgage
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value changes included in earnings for instruments for which the fair value option was elected	30,000,000	91,000,000
FVO valuation adjustments related to instrument-specific credit risk	1,000,000		$ 1,000,000
Commercial loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value changes included in earnings for instruments for which the fair value option was elected		(1,000,000)
Commercial loans held for sale \| Commercial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment		(3,000,000)
Fair value gains (losses)	1,000,000
Other Real Estate Owned
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value adjustment	(1,000,000)	(3,000,000)
Other Real Estate Owned \| Transfer
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Fair value gains (losses)	$ (5,000,000)	$ (1,000,000)