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Borrowings - Schedule of unamortized debt issuance cost (Details) - USD ($) $ in Thousands | Sep. 30, 2022 | Dec. 31, 2021
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Debt Instrument [Line Items] |  |
Total unamortized debt issuance costs | $ 3,165 | $ 2,283
Senior notes issued in 2017 | Senior Notes |  |
Debt Instrument [Line Items] |  |
Total unamortized debt issuance costs | 0 | 56
Subordinated notes issued in 2017 | Subordinated Debt |  |
Debt Instrument [Line Items] |  |
Total unamortized debt issuance costs | 0 | 549
Subordinated notes issued in 2020 | Subordinated Debt |  |
Debt Instrument [Line Items] |  |
Total unamortized debt issuance costs | 1,337 | 1,678
Subordinated notes issued in 2022 | Subordinated Debt |  |
Debt Instrument [Line Items] |  |
Total unamortized debt issuance costs | $ 1,828 | $ 0

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