Securities - Amortized Cost and Fair Value of Securities Available for Sale and Held To Maturity, Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Securities AFS, Amortized Cost
Maturing within one year	$ 24,490
Maturing after one year but within five years	127,044
Maturing after five years but within ten years	42,007
Maturing after ten years	192,839
Securities available-for-sale, amortized cost	386,380
Total securities available-for-sale, amortized cost	556,662	$ 621,588
Securities AFS, Fair Value
Maturing within one year	24,216
Maturing after one year but within five years	120,736
Maturing after five years but within ten years	38,417
Maturing after ten years	159,498
Total securities available-for-sale, fair value	342,867
Securities available for sale	502,583	559,182
Securities HTM, Amortized Cost
Maturing within one year	13,117
Maturing after one year but within five years	48,794
Maturing after five years but within ten years	91,368
Maturing after ten years	68,045
Total securities held-to-maturity, amortized cost	221,324
Amortized Cost	335,308	355,739
Securities HTM, Fair Value
Maturing within one year	12,967
Maturing after one year but within five years	46,630
Maturing after five years but within ten years	82,613
Maturing after ten years	57,339
Total securities held-to-maturity, fair value	199,549
Total securities held-to-maturity, fair value	293,242	301,860
U.S. agency residential mortgage-backed
Securities AFS, Amortized Cost
Available-for-sale securities, without single maturity, amortized cost	85,014
Total securities available-for-sale, amortized cost	85,014	80,589
Securities AFS, Fair Value
Available-for-sale securities, without single maturity, fair value.	78,196
Securities available for sale	78,196	71,137
Securities HTM, Amortized Cost
Held to maturity securities, without single maturity date, amortized cost	102,564
Amortized Cost	102,564	109,369
Securities HTM, Fair Value
Held to maturity securities, without single maturity date, fair value	82,849
Total securities held-to-maturity, fair value	82,849	84,738
U.S. agency commercial mortgage-backed
Securities AFS, Amortized Cost
Available-for-sale securities, without single maturity, amortized cost	8,362
Total securities available-for-sale, amortized cost	8,362	12,821
Securities AFS, Fair Value
Available-for-sale securities, without single maturity, fair value.	7,455
Securities available for sale	7,455	11,641
Securities HTM, Amortized Cost
Held to maturity securities, without single maturity date, amortized cost	4,002
Amortized Cost	4,002	4,120
Securities HTM, Fair Value
Held to maturity securities, without single maturity date, fair value	3,741
Total securities held-to-maturity, fair value	3,741	3,718
Private label mortgage-backed
Securities AFS, Amortized Cost
Available-for-sale securities, without single maturity, amortized cost	44,358
Total securities available-for-sale, amortized cost	44,358	74,268
Securities AFS, Fair Value
Available-for-sale securities, without single maturity, fair value.	41,936
Securities available for sale	41,936	70,035
Securities HTM, Amortized Cost
Held to maturity securities, without single maturity date, amortized cost	7,418
Amortized Cost	7,418	7,541
Securities HTM, Fair Value
Held to maturity securities, without single maturity date, fair value	7,103
Total securities held-to-maturity, fair value	7,103	6,990
Other asset backed
Securities AFS, Amortized Cost
Available-for-sale securities, without single maturity, amortized cost	32,548
Total securities available-for-sale, amortized cost	32,548	39,232
Securities AFS, Fair Value
Available-for-sale securities, without single maturity, fair value.	32,129
Securities available for sale	32,129	$ 38,516
Securities HTM, Amortized Cost
Held to maturity securities, without single maturity date, amortized cost	0
Securities HTM, Fair Value
Held to maturity securities, without single maturity date, fair value	$ 0

INDEPENDENT BANK CORP /MI/ 10-Q