Investment Securities, Securities Held-to-Maturity (Details) - USD ($) $ in Thousands		Sep. 30, 2024		Dec. 31, 2023		Dec. 31, 2022
Book Values, Estimated Fair Values and Unrealized Gains and Losses of Investments Classified as Held-to-maturity [Abstract]
Amortized cost		$ 780,510		$ 817,688
Gross unrecognized gains		210		137
Gross unrecognized losses		128,019		146,240
Fair value		652,701		671,585
Allowance for credit losses		450		450		$ 393
Mortgage-backed Securities [Member]
Book Values, Estimated Fair Values and Unrealized Gains and Losses of Investments Classified as Held-to-maturity [Abstract]
Amortized cost	[1]	635,630		664,728
Gross unrecognized gains	[1]	47		30
Gross unrecognized losses	[1]	116,056		132,043
Fair value	[1]	519,621		532,715
Allowance for credit losses		0	[1]	0	[1]	0
Collateralized Mortgage Obligations [Member]
Book Values, Estimated Fair Values and Unrealized Gains and Losses of Investments Classified as Held-to-maturity [Abstract]
Amortized cost	[1]	69,705		74,170
Gross unrecognized gains	[1]	0		0
Gross unrecognized losses	[1]	11,878		14,017
Fair value	[1]	57,827		60,153
Allowance for credit losses		0	[1]	0	[1]	0
Municipal Securities [Member]
Book Values, Estimated Fair Values and Unrealized Gains and Losses of Investments Classified as Held-to-maturity [Abstract]
Amortized cost		75,175		78,790
Gross unrecognized gains		163		107
Gross unrecognized losses		85		180
Fair value		75,253		78,717
Allowance for credit losses		$ 450		$ 450		$ 393

[1] All mortgage-backed securities and collateralized mortgage obligations were issued by an agency or government sponsored entity of the U.S. Government.