Securities - Narrative (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023 USD ($) debt_security	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) debt_security	Jun. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Schedule of Investments [Line Items]
Debt Securities, Available-for-sale, Allowance for Credit Loss	$ 0		$ 0		$ 0
Transferred Securities, Unrealized Loss, Before Tax	117,600,000		117,600,000		121,500,000
Securities transferred, Unrealized Loss, Net of Tax	92,900,000		92,900,000		96,000,000
Fair value of securities transferred from AFS to HTM			0		1,250,000,000
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]
Net gain (loss) on sale of securities AFS	3,455,000	$ 2,177,000	5,601,000	$ 3,720,000
Gross realized gains on AFS securities			1,400,000	4,000,000
Gross realized losses on AFS securities			7,000,000	290,000
Equity investments	9,572,000		9,572,000		11,181,000
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Sale of HTM portfolio			0	0
Interest receivable	48,265,000		48,265,000		49,350,000
Debt Securities, Held-to-maturity, Nonaccrual	0		0		0
FHLB stock with other-than-temporary impairment	0		0
Other-than-temporarily impaired equity investments	$ 0		$ 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | debt_security	524		524
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 207,113,000	172,289,000	$ 207,113,000	172,289,000	199,252,000	$ 201,753,000
Less: Net gains recognized during the period on equity investments sold during the period	2,642,000	0	5,058,000	0
State and political subdivisions
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)	0	0	0	0
Corporate bonds and other
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)	0	$ 0	0	$ 0
Asset Pledged as Collateral
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities	2,240,000,000		2,240,000,000		1,820,000,000
Financial Asset, Past Due
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Securities held to maturity (estimated fair value of $138,879)	0		0		0
Available-for-sale Securities
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Interest receivable	16,300,000		16,300,000		16,900,000
Held-to-maturity Securities
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Interest receivable	$ 13,400,000		$ 13,400,000		$ 13,600,000