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Commitments to sell real estate loans net.

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Interest rate swap agreements used for interest rate risk management.

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Amount before allowance of consumer installment revolving and home equity loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts.

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Other credit-related commitments.

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Other financial instruments.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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Amount after offset of short term borrowing where a bank borrows, at the federal funds rate, from another bank and securities that an entity sells and agrees to repurchase at a specified date for a specified price.

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For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

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Fair Value Measurements - Carrying Amounts and Estimated Fair Value for Financial Instrument Assets (Liabilities) (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Financial assets:
Interest-bearing deposits at banks	$ 41,872,304	$ 23,663,810
Investment securities	7,155,860	7,045,697
Loans and leases:
Loans and leases	93,136,678	98,875,788
Allowance for credit losses	(1,469,226)	(1,736,387)	$ (1,051,071)	$ (1,019,444)
Loans and leases, net	91,443,226	96,799,480
Financial liabilities:
Noninterest-bearing deposits	(60,131,480)	(47,572,884)
Savings and interest-checking deposits	(68,603,966)	(67,680,840)
Time deposits	(2,807,963)	(3,899,910)
Deposits at Cayman Islands office		(652,104)
Long-term borrowings	(3,485,369)	(4,382,193)
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets:
Cash and cash equivalents	1,205,269	1,497,457
Trading account assets	49,545	50,060
Investment securities	68,850	63,129
Significant Observable Inputs (Level 2) [Member]
Financial assets:
Cash and cash equivalents	132,308	55,286
Interest-bearing deposits at banks	41,872,304	23,663,810
Trading account assets	418,486	1,018,521
Investment securities	7,066,293	7,005,571
Loans and leases:
Loans and leases, net	4,949,028	4,413,566
Accrued interest receivable	335,162	419,936
Financial liabilities:
Noninterest-bearing deposits	(60,131,480)	(47,572,884)
Savings and interest-checking deposits	(68,603,966)	(67,680,840)
Time deposits	(2,810,143)	(3,919,367)
Deposits at Cayman Islands office		(652,104)
Short-term borrowings	(47,046)	(59,482)
Long-term borrowings	(3,562,223)	(4,490,433)
Accrued interest payable	(40,866)	(59,916)
Trading account liabilities	(83,434)	(116,902)
Other financial instruments:
Commitments to sell real estate loans	7,525	(18,429)
Interest rate swap agreements used for interest rate risk management	(207)	1,076
Significant Unobservable Inputs (Level 3) [Member]
Financial assets:
Investment securities	57,333	70,289
Loans and leases:
Consumer loans	18,121,363	16,554,050
Loans and leases, net	87,348,549	93,266,904
Other financial instruments:
Commitments to originate real estate loans for sale	6,440	43,234
Other credit-related commitments	(123,032)	(133,354)
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	1,337,577	1,552,743
Interest-bearing deposits at banks	41,872,304	23,663,810
Trading account assets	468,031	1,068,581
Investment securities	7,155,860	7,045,697
Loans and leases:
Consumer loans	17,974,953	16,570,421
Allowance for credit losses	(1,469,226)	(1,736,387)
Loans and leases, net	91,443,226	96,799,480
Accrued interest receivable	335,162	419,936
Financial liabilities:
Noninterest-bearing deposits	(60,131,480)	(47,572,884)
Savings and interest-checking deposits	(68,603,966)	(67,680,840)
Time deposits	(2,807,963)	(3,899,910)
Deposits at Cayman Islands office		(652,104)
Short-term borrowings	(47,046)	(59,482)
Long-term borrowings	(3,485,369)	(4,382,193)
Accrued interest payable	(40,866)	(59,916)
Trading account liabilities	(83,434)	(116,902)
Other financial instruments:
Commitments to originate real estate loans for sale	6,440	43,234
Commitments to sell real estate loans	7,525	(18,429)
Other credit-related commitments	(123,032)	(133,354)
Interest rate swap agreements used for interest rate risk management	(207)	1,076
Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	1,337,577	1,552,743
Interest-bearing deposits at banks	41,872,304	23,663,810
Trading account assets	468,031	1,068,581
Investment securities	7,192,476	7,138,989
Loans and leases:
Consumer loans	18,121,363	16,554,050
Loans and leases, net	92,297,577	97,680,470
Accrued interest receivable	335,162	419,936
Financial liabilities:
Noninterest-bearing deposits	(60,131,480)	(47,572,884)
Savings and interest-checking deposits	(68,603,966)	(67,680,840)
Time deposits	(2,810,143)	(3,919,367)
Deposits at Cayman Islands office		(652,104)
Short-term borrowings	(47,046)	(59,482)
Long-term borrowings	(3,562,223)	(4,490,433)
Accrued interest payable	(40,866)	(59,916)
Trading account liabilities	(83,434)	(116,902)
Other financial instruments:
Commitments to originate real estate loans for sale	6,440	43,234
Commitments to sell real estate loans	7,525	(18,429)
Other credit-related commitments	(123,032)	(133,354)
Interest rate swap agreements used for interest rate risk management	(207)	1,076
Commercial Loans and Leases [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Loans and leases:
Loans and leases	23,285,224	27,220,699
Commercial Loans and Leases [Member] \| Carrying Amount [Member]
Loans and leases:
Loans and leases	23,473,324	27,574,564
Commercial Loans and Leases [Member] \| Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount [Member]
Loans and leases:
Loans and leases	23,285,224	27,220,699
Commercial [Member] \| Significant Observable Inputs (Level 2) [Member]
Loans and leases:
Loans and leases	425,010	277,911
Commercial [Member] \| Significant Unobservable Inputs (Level 3) [Member]
Loans and leases:
Loans and leases	34,305,181	36,538,669
Commercial [Member] \| Carrying Amount [Member]
Loans and leases:
Loans and leases	35,389,730	37,637,889
Commercial [Member] \| Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount [Member]
Loans and leases:
Loans and leases	34,730,191	36,816,580
Residential Real Estate Loans \| Significant Observable Inputs (Level 2) [Member]
Loans and leases:
Loans and leases	4,524,018	4,135,655
Residential Real Estate Loans \| Significant Unobservable Inputs (Level 3) [Member]
Loans and leases:
Loans and leases	11,636,781	12,953,486
Residential Real Estate Loans \| Carrying Amount [Member]
Loans and leases:
Loans and leases	16,074,445	16,752,993
Residential Real Estate Loans \| Cumulative Amount of Fair Value Hedging Adjustment Increasing (Decreasing) the Carrying Amount [Member]
Loans and leases:
Loans and leases	$ 16,160,799	$ 17,089,141