Derivative Financial Instruments - Summary of Derivative Activity and Related Impact on Consolidated Statements of Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Interest rate risks | Derivatives designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	$ 17,176	$ 2,089
Interest rate risks | Derivatives designated as hedging instruments | Reclassification out of Accumulated Other Comprehensive Income | Interest income - loans
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	15,657	2,089
Interest rate risks | Derivatives designated as hedging instruments | Change In Fair Value Of Interest Rate Swaps Hedging Investment Securities | Interest income - loans
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	18,494	0
Interest rate risks | Derivatives designated as hedging instruments | Change In Fair Value Of Hedged Investment Securities | Interest income - loans
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	(16,975)	0
Currency exchange risk | Derivatives not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	(1,276)	293
Currency exchange risk | Derivatives not designated as hedging instruments | Revaluations of internal foreign currency instruments, net | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	(28,129)	(8,375)
Currency exchange risk | Derivatives not designated as hedging instruments | Foreign exchange forward contracts, net | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	26,853	8,668
Other derivative instruments | Derivatives not designated as hedging instruments
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	324	(537)
Other derivative instruments | Derivatives not designated as hedging instruments | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	4,521	(4,345)
Other derivative instruments | Derivatives not designated as hedging instruments | Revaluations of internal foreign currency instruments, net | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	(2,427)	(8,284)
Other derivative instruments | Derivatives not designated as hedging instruments | Foreign exchange forward contracts, net | Other noninterest income
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	2,751	7,747
Equity warrant assets
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	29,445	(18,574)
Equity warrant assets | Derivatives not designated as hedging instruments | Gains on equity warrant assets, net
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gains (losses) on derivatives	$ 221,685	$ 13,395