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Summary of Significant Accounting Policies (Details) $ / shares in Units, $ in Thousands		3 Months Ended
	Feb. 08, 2021 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) portfolioSegment classOfPortfolioSegment branch	Sep. 30, 2023 USD ($)
Accounting Policies [Line Items]
Number of bank branches \| branch		198
Dividend rate	4.875%
Proceeds from issuance of preferred stock, net	$ 293,325
Cash collateral		$ 229,100	$ 326,750
Fair value of NAV		36,708
Remaining unfunded commitment		$ 5,578
Number of portfolio segments for loans held for investment \| portfolioSegment		2
Number of classes disaggregating the commercial loan portfolio \| classOfPortfolioSegment		5
Number of classes disaggregating the consumer loan portfolio \| classOfPortfolioSegment		5
Loans in process		$ 1,516,522	1,895,940
Financing Receivable
Accounting Policies [Line Items]
Loans in process		$ 3,180,001	$ 3,625,333
Public Offering
Accounting Policies [Line Items]
Number of depositary shares \| shares	12,000,000
Percentage of preferred stock	2.50%
Public offering price (in usd per share) \| $ / shares	$ 25.00
Series A Preferred Stock \| Public Offering
Accounting Policies [Line Items]
Number of depositary shares \| shares	300,000