Derivatives - Gains (Losses) in Cash Flow Hedge and Net Investment Hedge (Details) - Derivative instruments designated as hedging instruments - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Interest rate contracts \| Cash Flow Hedging
Derivative [Line Items]
Losses recognized in AOCI:	$ (62,715)	$ (48,325)	$ (129,329)	$ (88,771)
Gains (losses) reclassified from AOCI into earnings:	(24,059)	(1,619)	(54,955)	1,601
Interest rate contracts \| Cash Flow Hedging \| Interest expense (for cash flow hedges on borrowings)
Derivative [Line Items]
Gains (losses) reclassified from AOCI into earnings:	0	1,251	696	1,385
Interest rate contracts \| Cash Flow Hedging \| Interest and dividend income (for cash flow hedges on loans)
Derivative [Line Items]
Gains (losses) reclassified from AOCI into earnings:	(24,059)	(2,870)	(57,265)	216
Interest rate contracts \| Cash Flow Hedging \| Noninterest income
Derivative [Line Items]
Gains (losses) reclassified from AOCI into earnings:	0	0	1,614	0
Foreign exchange contracts \| Net Investment Hedging
Derivative [Line Items]
Gains recognized in AOCI	$ 63	$ 4,343	$ 2,886	$ 6,027

Other comprehensive income (loss) on derivatives instrument designated and qualifying in Net Investment Hedge Period Increase (Decrease).

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480237/815-40-50-5

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- Definition

Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4C

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480627/815-20-45-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4A

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 10A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-10A

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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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