Interest-Bearing Deposits - Components of Interest-Bearing Deposits (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Deposits [Abstract]
Interest-bearing demand deposits	$ 1,795,513	$ 688,596
Savings deposits	4,241,762	4,989,342
Time deposits	1,840,923	1,750,466
Total interest-bearing deposits	7,878,198	7,428,404
Interest Bearing Deposits [Line Items]
Interest-bearing demand deposits	1,795,513	688,596
Savings deposits	4,241,762	4,989,342
Time deposits	1,840,923	1,750,466
Interest-bearing	$ 7,878,198	7,428,404
Impact of Sweeps
Deposits [Abstract]
Interest-bearing demand deposits		1,167,037
Savings deposits		(1,167,037)
Time deposits		0
Total interest-bearing deposits		0
Interest Bearing Deposits [Line Items]
Interest-bearing demand deposits		1,167,037
Savings deposits		(1,167,037)
Time deposits		0
Interest-bearing		0
Net of Sweeps
Deposits [Abstract]
Interest-bearing demand deposits		1,855,633
Savings deposits		3,822,305
Time deposits		1,750,466
Total interest-bearing deposits		7,428,404
Interest Bearing Deposits [Line Items]
Interest-bearing demand deposits		1,855,633
Savings deposits		3,822,305
Time deposits		1,750,466
Interest-bearing		$ 7,428,404

Interest Bearing Deposits [Line Items]

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- Definition

Savings Deposits

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- References

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- Definition

Total amount of interest-bearing domestic deposit liabilities, which may include brokered, retail, demand, checking, notice of withdrawal, money market and other interest-bearing deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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- Definition

Amount of money in interest-bearing domestic accounts that entitle the depositor to withdraw funds at any time without prior notice, also known as demand deposits.

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- Definition

Amount of time deposit liabilities, including certificates of deposit.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478353/942-405-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(12))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

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