Investment securities available for sale - Summary of amortized cost and estimated fair value of investment securities available for sale (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Amortized Cost
Less than one year	$ 26
One to five years	60,537
Five to ten years	16,699
More than ten years	64,306
Total	141,568
Fair Value
Less than one year	25
One to five years	57,614
Five to ten years	16,150
More than ten years	57,834
Total	$ 131,623	$ 94,699

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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