Deferred stock units issued.

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- Definition

Defined benefit plan cash value income.

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- Definition

Defined benefit plan expenses.

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Matching and profit sharing vesting period.

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- Definition

Post retirement benefits payable.

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- Definition

Share based compensation arrangement by share based payment award equity instruments units Remaining in equity based incentive plan for cash settlement.

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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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- Definition

Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

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Amount of liabilities classified as other.

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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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No definition available.

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Per share or per unit amount of equity securities issued.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Employee benefit plans (Details)		12 Months Ended
Employee benefit plans (Details)	Jun. 28, 2016	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($)	Dec. 31, 2014 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Discretionary contribution percentage			50.00%	25.00%
Maximum percentage of amount to be contributed by the employer			6.00%	6.00%
Matching and profit sharing vesting period			3 years	5 years
Contribution provided by the bank to the plan		$ 3,198,000	$ 2,325,000	$ 2,211,000
Post retirement benefits payable		1,112,000	1,315,000
Expense related to plans		29,000	1,000	4,000
Payments to participants		131,000	150,000	191,000
Cash surrender value on bank owned life insurance		71,977,000	11,357,000
Cash value income		1,556,000	240,000	158,000
Deferred compensation		2,261,000	1,718,000
Salaries, commissions and employee benefits		$ 233,768,000	152,084,000	136,892,000
2012 EBI Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants authorized under the plan (in shares) \| shares		0
Deferred Compensation Plans and Agreements
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments to participants			1,191,000	1,818,000
Liability for cash-settled awards			$ 993,000
Number of units remaining in equity based incentive plan for cash settlement \| shares			29,172
Salaries, commissions and employee benefits			$ 484,000	$ 3,787,000
Deferred Compensation Plans and Agreements \| 2012 EBI Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock split ratio	100
Deferred Compensation Plans and Agreements \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock split ratio			1
Deferred compensation			$ 3,000,000		$ 3,000,000
Deferred stock units issued (in shares) \| shares		0	157,895
IPO price (USD per share) \| $ / shares					$ 19.00