Other assets and other liabilities - Summary of Other Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Other Assets And Other Liabilities [Abstract]
Cash surrender value on bank owned life insurance	$ 11,115	$ 10,873
Prepaid expenses	3,283	2,477
Software	1,313	1,962
Mortgage lending receivable	3,876	3,703
Derivatives (See Note 16)	14,316	9,690
FHLB lender risk account receivable (See Note 1)	5,225	0
Other assets	30,974	15,511
Total other assets	$ 70,102	$ 44,216

Deposits With Federal Home Loan Banks

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Other assets and other liabilities.

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Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Amount before allowance of revolving credit lines for to originate and purchase financial assets including, but not limited to, mortgage loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

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Amount of assets classified as other.

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Amount of other miscellaneous assets.

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Carrying amount as of the balance sheet date of expenditures made in advance of when the economic benefit of the cost will be realized, and which will be expensed in future periods with the passage of time or when a triggering event occurs.

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