Investment Securities - Amortized cost of held to maturity debt securities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	$ 67,555	$ 63,837
AAA/AA/A
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	66,140
UNRATED
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	1,415
U.S. Agency
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	2,500	2,500
U.S. Agency \| AAA/AA/A
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	2,500
U.S. Agency mortgage-backed securities
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	31,552	26,966
U.S. Agency mortgage-backed securities \| AAA/AA/A
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	31,552
Municipal
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	30,088	30,959
Municipal \| AAA/AA/A
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	30,088
Corporate bonds and other securities
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	3,415	$ 3,412
Corporate bonds and other securities \| AAA/AA/A
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	2,000
Corporate bonds and other securities \| UNRATED
Schedule of Held-to-Maturity Securities [Line Items]
Investment securities - HTM, Carrying Value	$ 1,415

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

AMERISERV FINANCIAL INC /PA/ 10-Q