DEFINED BENEFIT PENSION PLAN (Details)	12 Months Ended
Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($)
Defined Benefit Pension Plan
Number of years over which anticipated pension distributions disclosed \| item	5
Anticipated distributions from the plan
2019	$ 136,000
2020	132,000
2021	131,000
2022	137,000
2023	143,000
2024-2028	823,000
Total	1,502,000
Peninsula Financial Corporation noncontributory defined benefit pension plan
Defined Benefit Pension Plan
Expected contributions to the plan next fiscal year	22,000
Change in benefit obligation:
Benefit obligation, beginning of year	3,331,000	$ 3,187,000
Interest cost	109,000	118,000
Actuarial (gain) loss	(315,000)	161,000
Benefits paid	(134,000)	(135,000)
Benefit obligation at end of year	2,991,000	3,331,000
Change in plan assets
Fair value of plan assets, beginning of year	2,191,000	2,049,000
Actual return on plan assets	(134,000)	259,000
Employer contributions	64,000	18,000
Benefits paid	(134,000)	(135,000)
Fair value of plan assets at end of year	1,987,000	2,191,000
Funded status, included with other liabilities	$ (1,004,000)	$ (1,140,000)
Assumptions in the actuarial valuation
Weighted average discount rate	4.02%	3.33%
Expected long-term rate of return on plan assets	8.00%	8.00%
Peninsula Financial Corporation noncontributory defined benefit pension plan \| Equity securities \| Plan
Plan assets
Actual Allocation	59.00%
Peninsula Financial Corporation noncontributory defined benefit pension plan \| Equity securities \| Plan \| Minimum
Plan assets
Target Allocation	50.00%
Peninsula Financial Corporation noncontributory defined benefit pension plan \| Equity securities \| Plan \| Maximum
Plan assets
Target Allocation	70.00%
Peninsula Financial Corporation noncontributory defined benefit pension plan \| Fixed income securities \| Plan
Plan assets
Actual Allocation	41.00%
Peninsula Financial Corporation noncontributory defined benefit pension plan \| Fixed income securities \| Plan \| Minimum
Plan assets
Target Allocation	30.00%
Peninsula Financial Corporation noncontributory defined benefit pension plan \| Fixed income securities \| Plan \| Maximum
Plan assets
Target Allocation	50.00%

Represents the number of years over which the anticipated distributions on pension plans is being disclosed

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Amount of benefits from a defined benefit plan expected to be paid. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of contribution received by defined benefit plan from employer which increases plan assets.

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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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Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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