Number of debt securities with gross losses.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(9)(a))
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-Publisher FASB
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-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-URI https://asc.fasb.org/extlink&oid=126953954&loc=SL114868664-224227

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- 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 https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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-Publisher FASB
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-Publisher FASB
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-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

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- Definition

Amount of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

+ References

No definition available.

+ Details

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- Definition

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

No definition available.

+ Details

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- 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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Investment Securities - Additional Information (Detail)	3 Months Ended		6 Months Ended
Investment Securities - Additional Information (Detail)	Jun. 30, 2022 USD ($) Security	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) Security	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Investment Holdings [Line Items]
Gross realized gains(loss) on sale of investment securities	$ 0	$ 0	$ 0	$ 0
Gains (losses) on equity securities	$ (62,000)	$ (10,655,000)	$ (805,000)	$ (22,937,000)
Number of debt securities with aggregate gross unrealized losses \| Security	3,914		3,914
Unrealized losses on individual debt securities			$ 866,000,000
Cost method equity securities	$ 622,000,000		622,000,000
Maximum [Member]
Investment Holdings [Line Items]
Gains (losses) on equity securities	(1,000,000)		(1,000,000)
Available-for-Sale Securities [Member]
Investment Holdings [Line Items]
Allowance for credit losses	$ 0		$ 0		$ 0