Derivative Financial Instruments - Schedule of Effect of Derivative Instruments on the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative	$ (9,506)	$ 4,048
Gain (Loss) Reclassified from AOCI into Income	669	149
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	603	3,682
Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	52,821	44,264
Gain (Loss) Recognized in Income on Related Hedged Items	(53,073)	(43,966)
Interest rate contracts \| Other income/(expense) \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	501	385
Interest rate contracts \| Interest income/(expense)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative	(9,506)	4,048
Gain (Loss) Reclassified from AOCI into Income	669	149
Mortgage contracts \| Mortgage banking revenue \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	130	3,261
Foreign currency contracts \| Other income/(expense) \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	(28)	36
Interest rate swaps on borrowings \| Interest income/(expense) \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	(4,833)	(1,575)
Gain (Loss) Recognized in Income on Related Hedged Items	4,956	1,578
Interest rate swaps on investment securities \| Interest income/(expense) \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	57,654	45,839
Gain (Loss) Recognized in Income on Related Hedged Items	$ (58,029)	$ (45,544)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period.

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

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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.

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