Carrying value of available for sale securities pledged.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Total amount of accumulated unrealized gain on investments in debt and equity securities before taxes.

+ References

No definition available.

+ Details

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- Definition

Carrying value of investment securities pledged to secure borrowings from certain various FHLBs, repurchase agreements, governmental deposits, interest rate swap agreements and available lines of credit.

+ References

No definition available.

+ Details

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- Definition

The number of individual investment securities in gross unrealized loss positions. Unrealized losses occur when the amortized cost of an investment security is greater than its estimated fair value.

+ References

No definition available.

+ Details

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- Definition

Number of single investment securities that exceeded ten percent of shareholders' equity.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of realized gain (loss) on investment in debt and equity securities.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aaa)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5086-111524

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Period Type:	instant

- Details

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- Details

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- Details

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Investment Securities - Additional Information (Detail)	12 Months Ended
Investment Securities - Additional Information (Detail)	Dec. 31, 2021 USD ($) Investment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Investment Holdings [Line Items]
Gross realized gains(loss) on sale of investment securities	$ 0	$ 0	$ 0
Number of investment securities with aggregate gross unrealized losses \| Investment	371
Unrealized losses on individual investment securities	$ 32,000,000
Cost method investment securities	388,000,000
Investment securities pledged to secure debt carrying value	5,100,000,000
Pledged securities that can be sold or repledged	96,128,000	105,136,000
Available-for-Sale Securities [Member]
Investment Holdings [Line Items]
Allowance for credit losses	0	$ 0
Investment securities pledged to secure debt carrying value	$ 2,400,000,000
Government Agency [Member]
Investment Holdings [Line Items]
Number of investment securities that exceeded ten percent of shareholders' equity \| Investment	0
Non-U.S. Government [Member]
Investment Holdings [Line Items]
Number of investment securities that exceeded ten percent of shareholders' equity \| Investment	0
Government Issued or Guaranteed [Member]
Investment Holdings [Line Items]
Number of investment securities that exceeded ten percent of shareholders' equity \| Investment	0