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EMPLOYEE BENEFIT PLANS (Tables) | 12 Months Ended
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Dec. 31, 2017
Retirement Benefits [Abstract] |
Schedule of Multiemployer Plan |
|  |  | Funding Status of Pension Plan |  | FIP/RP Status Pending/ Implemented |  | Surcharge Imposed |  | Expiration Date of Collective- Bargaining Agreement |  | Minimum Contributions Required for Future Periods
| EIN/Pension Plan Number |  | 2017 |  | 2016 |
Pentegra defined benefit plan for financial institutions | 13-5645888/333 |  | At least 80 percent |  | At least 80 percent |  | No |  | No |  | N/A |  | $ | — |
Schedule of Multiemployer Plan Contributions | The Company’s contributions to the Pension Plans were as follows for the periods indicated:
|  |  |  |  |  |  | Required Contributions - Plan Year Allocation
| Cash Payment |  | Future period funding |  | 2017-2018 |  | 2016-2017 |  | 2015-2016
| (Dollars in thousands)
2017 | $ | 6,432 |  |  | $ | 5,000 |  |  | $ | 1,432 |  |  | $ | — |  |  | $ | — |
2016 | $ | 6,245 |  |  | $ | 4,000 |  |  | $ | — |  |  | $ | 2,245 |  |  | $ | — |
2015 | $ | 2,983 |  |  | $ | 1,215 |  |  | $ | — |  |  | $ | — |  |  | $ | 1,768 |
Schedule of Supplemental Retirement Expense and Contributions Paid | The following table shows the defined benefit supplemental retirement expense, and the contributions paid to the plans which were used only to pay the current year benefits as of the dates indicated:
| 2017 |  | 2016 |  | 2015
| (Dollars in thousands)
Retirement expense | $ | 1,580 |  |  | $ | 1,513 |  |  | $ | 1,834 |
Contributions paid | $ | 367 |  |  | $ | 320 |  |  | $ | 276 |
Schedule of Expected Benefit Payments | Expected future benefit payments for the defined benefit supplemental executive retirement plans are presented below:
| Defined Benefit Supplemental Executive Retirement Plans Expected Benefit Payments
| (Dollars in thousands)
2018 | $ | 408 |
2019 | $ | 481 |
2020 | $ | 467 |
2021 | $ | 461 |
2022 | $ | 454 |
2023-2027 | $ | 5,366 |
Schedule of Supplemental Executive Retirement Plans | The following table illustrates the status of the defined benefit supplemental executive retirement plans at December 31 for the years presented:
| Defined Benefit Supplemental Executive Retirement Benefits
| 2017 |  | 2016 |  | 2015
| (Dollars in thousands)
Change in accumulated benefit obligation |  |  |  |  |
Benefit obligation at beginning of year | $ | 14,177 |  |  | $ | 13,290 |  |  | $ | 12,537 |
Accumulated service cost | 423 |  |  | 395 |  |  | 742 |
Interest cost | 547 |  |  | 539 |  |  | 470 |
Actuarial loss/(gain) | 969 |  |  | 273 |  |  | (183 | )
Benefits paid | (367 | ) |  | (320 | ) |  | (276 | )
Accumulated benefit obligation at end of year | $ | 15,749 |  |  | $ | 14,177 |  |  | $ | 13,290 |
Change in plan assets |  |  |  |  |
Fair value of plan assets at beginning of year | $ | — |  |  | $ | — |  |  | $ | — |
Employer contribution | 367 |  |  | 320 |  |  | 276 |
Benefits paid | (367 | ) |  | (320 | ) |  | (276 | )
Fair value of plan assets at end of year | $ | — |  |  | $ | — |  |  | $ | — |
Funded status at end of year | $ | (15,749 | ) |  | $ | (14,177 | ) |  | $ | (13,290 | )
Assets | — |  |  | — |  |  | — |
Liabilities | (15,749 | ) |  | (14,177 | ) |  | (13,290 | )
Accrued benefit cost | $ | (15,749 | ) |  | $ | (14,177 | ) |  | $ | (13,290 | )
Amounts recognized in accumulated other comprehensive income (“AOCI”) |  |  |  |  |
Net loss | $ | 3,465 |  |  | $ | 2,830 |  |  | $ | 2,859 |
Prior service cost | 1,047 |  |  | 1,323 |  |  | 1,599 |
Amounts recognized in AOCI | $ | 4,512 |  |  | $ | 4,153 |  |  | $ | 4,458 |
Information for plans with an accumulated benefit obligation in excess of plan assets |  |  |  |  |
Projected benefit obligation | $ | 15,749 |  |  | $ | 14,177 |  |  | $ | 13,290 |
Accumulated benefit obligation | $ | 15,749 |  |  | $ | 14,177 |  |  | $ | 13,290 |
Net periodic benefit cost |  |  |  |  |
Service cost | $ | 423 |  |  | $ | 395 |  |  | $ | 742 |
Interest cost | 547 |  |  | 539 |  |  | 470 |
Amortization of prior service cost | 276 |  |  | 276 |  |  | 305 |
Recognized net actuarial loss | 334 |  |  | 303 |  |  | 317 |
Net periodic benefit cost | $ | 1,580 |  |  | $ | 1,513 |  |  | $ | 1,834 |
Amounts in accumulated other comprehensive income expected to be recognized in net periodic benefit cost over next fiscal year |  |  |  |  |
Net actuarial loss | $ | 415 |  |  | $ | 338 |  |  | $ | 270 |
Net prior service cost | $ | 276 |  |  | $ | 276 |  |  | $ | 276 |
Discount rate used for benefit obligation | 2.48-3.45% |  |  | 2.49-3.94% |  |  | 2.49-4.16% |
Discount rate used for net periodic benefit cost | 2.49-3.94% |  |  | 2.49-4.16% |  |  | 2.24-3.84% |
Rate of compensation increase | n/a |  |  | n/a |  |  | n/a |

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- Definition Tabular disclosure of the costs. including defined benefit pension plan cost, defined contribution plan cost, other postretirement benefit plan cost, and net periodic benefit cost and plan contributions related to the various types of retirement plans. + References No definition available. + Details
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- Definition Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2439-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2410-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=77993564&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the quantitative and qualitative information related to multiemployer plans in which the employer participates. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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