Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments - Unrealized and realized gains and losses recognized in net income on equity securities (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Investment Securities, Equity Securities with Readily Determinable Fair Values and Other Investments
Equity Securities	$ 5,538,000		$ 5,538,000		$ 5,417,000
Summary of unrealized and realized gains and losses recognized in net income on equity securities
Net gains (losses) recognized during the period on equity securities	201,000	$ (142,000)	121,000	$ (200,000)
Unrealized gains (losses) recognized during the reporting period on equity securities still held at the reporting date	$ 201,000	$ (142,000)	$ 121,000	$ (200,000)