Derivative Financial Instruments - Schedule of Effect of Derivative Instruments on the Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative	$ (164)	$ (11)	$ 2,612	$ 7,546
Gain (Loss) Reclassified from AOCI into Income	1,578	1,550	3,483	3,651
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	1,103	(2,757)	(952)	8,687
Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	4,659		1,842
Gain (Loss) Recognized in Income on Related Hedged Items	(4,153)		(1,386)
Interest rate swaps on borrowings \| Interest income/(expense) \| Fair value hedges
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	(991)	(1,294)	(3,817)	8,678
Gain (Loss) Recognized in Income on Related Hedged Items	943	1,290	3,772	(8,726)
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	5,650		5,659
Gain (Loss) Recognized in Income on Related Hedged Items	(5,096)		(5,158)
Interest rate contracts \| Interest income/(expense)
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Other Comprehensive Income on Derivative	(164)	(11)	2,612	7,546
Gain (Loss) Reclassified from AOCI into Income	1,578	1,550	3,483	3,651
Interest rate contracts \| Other income/(expense) \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	46	5	356	(582)
Mortgage contracts \| Mortgage banking revenue \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	1,054	(2,811)	(1,262)	9,244
Foreign currency contracts \| Other income/(expense) \| Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) Recognized in Income on Derivative	$ 3	$ 49	$ (46)	$ 25

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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