Commitments and Contingencies - Amounts Related to Fair Value of Derivative Financial Instruments (Details) - USD ($)	Dec. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Hedged item—subordinated debt and loans:
Derivative [Line Items]
Other Assets	$ 0		$ 0
Other Liabilities	50,922,000		154,204,000
Derivative—interest rate swaps:
Derivative [Line Items]
Notional Amount		$ 300,000,000
Derivatives designated as hedging instruments:
Derivative [Line Items]
Notional Amount	1,000,000,000		1,100,000,000
Derivatives not designated as hedging instruments:
Derivative [Line Items]
Notional Amount	10,301,772,000		9,211,043,000
Derivatives not designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Notional Amount	10,301,460,000		8,889,557,000
Derivatives not designated as hedging instruments: | Mortgage banking derivatives
Derivative [Line Items]
Notional Amount	312,000		321,486,000
Other Assets | Derivatives designated as hedging instruments:
Derivative [Line Items]
Other Assets	0		0
Other Assets | Derivatives not designated as hedging instruments:
Derivative [Line Items]
Other Assets	181,500,000		387,452,000
Other Assets | Derivatives not designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Other Assets	181,012,000		387,008,000
Other Assets | Derivatives not designated as hedging instruments: | Mortgage banking derivatives
Derivative [Line Items]
Other Assets	488,000		444,000
Other Liabilities | Derivatives designated as hedging instruments:
Derivative [Line Items]
Other Liabilities	3,645,000		179,000
Other Liabilities | Derivatives not designated as hedging instruments:
Derivative [Line Items]
Other Liabilities	48,731,000		156,102,000
Other Liabilities | Derivatives not designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Other Liabilities	47,277,000		154,025,000
Other Liabilities | Derivatives not designated as hedging instruments: | Mortgage banking derivatives
Derivative [Line Items]
Other Liabilities	1,454,000		2,077,000
Cash flow hedge | Derivatives designated as hedging instruments: | Hedged item—subordinated debt and loans:
Derivative [Line Items]
Notional Amount	700,000,000		1,100,000,000
Cash flow hedge | Derivatives designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Notional Amount	700,000,000
Cash flow hedge | Other Assets | Derivatives designated as hedging instruments: | Hedged item—subordinated debt and loans:
Derivative [Line Items]
Other Assets	0		0
Cash flow hedge | Other Liabilities | Derivatives designated as hedging instruments: | Hedged item—subordinated debt and loans:
Derivative [Line Items]
Other Liabilities	310,000		179,000
Fair value hedge | Derivatives designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Notional Amount	300,000,000		0
Fair value hedge | Derivatives not designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Notional Amount	10,400,000
Fair value hedge | Other Assets | Derivatives designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Other Assets	0		0
Fair value hedge | Other Liabilities | Derivatives designated as hedging instruments: | Derivative—interest rate swaps:
Derivative [Line Items]
Other Liabilities	$ 3,335,000		$ 0