Investment securities - Maturities (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Investment securities
Acquisition Cost, Original maturities of 90 days or less	$ 38,111
Acquisition Cost, Original maturities of 91-365 days	74,249
Acquisition Cost, Original maturities of 365+ days	39,778
Acquisition Cost	152,138
Fair Value, Original maturities of 90 days or less	38,186
Fair Value, Original maturities of 91-365 days	74,200
Fair Value, Original maturities of 365+ days	39,197
Estimated Fair Value	$ 151,583

Cost of the investment.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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Fair value of investment measured at amortized cost (held-to-maturity), maturing in 90 to 365 days.

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Fair value of investment measured at amortized cost (held-to-maturity), maturing after 365 days.

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Amount excluding accrued interest, of investment at cost (held-to-maturity), maturing in 90 days or less.

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Amount excluding accrued interest, of investment at cost (held-to-maturity), maturing after 365 days.

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Amount excluding accrued interest, of investment at cost (held-to-maturity), maturing in 90 to 365 days.

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