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Employee Benefits (Tables) | 12 Months Ended
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Dec. 31, 2017
Retirement Benefits [Abstract] |
Benefit Obligation and Plan Assets Deriving Funded Status, in Other Liabilities | The following table summarizes the activity in the benefit obligation and Plan assets deriving the funded status, which is recorded in other liabilities in the Consolidated Balance Sheets:
(dollars in thousands) | 2017 |  |  | 2016 |
Change in Projected Benefit Obligation |  |  |
Projected benefit obligation at beginning of year | $ | 105,834 |  |  | $ | 109,747 |
Service cost | — |  |  | 463 |
Interest cost | 4,100 |  |  | 4,296 |
Actuarial loss | 4,974 |  |  | 3,575 |
Curtailments | — |  |  | (6,997 | )
Benefits paid | (8,244 | ) |  | (5,250 | )
Projected Benefit Obligation at End of Year | $ | 106,664 |  |  | $ | 105,834 |
Change in Plan Assets |  |  |
Fair value of plan assets at beginning of year | $ | 87,711 |  |  | $ | 84,585 |
Actual return on plan assets | 7,687 |  |  | 8,376 |
Benefits paid | (8,244 | ) |  | (5,250 | )
Fair Value of Plan Assets at End of Year | $ | 87,154 |  |  | $ | 87,711 |
Funded Status | $ | (19,510 | ) |  | $ | (18,123 | )
Accumulated Other Comprehensive Income (Loss) | The following table sets forth the amounts recognized in accumulated other comprehensive (loss) income at December 31:
(dollars in thousands) | 2017 |  |  | 2016 |
Prior service credit | $ | — |  |  | $ | — |
Net actuarial loss | (27,825 | ) |  | (26,013 | )
Total (Before Tax Effects) | $ | (27,825 | ) |  | $ | (26,013 | )
Actuarial Weighted Average Assumptions Used in Determining Benefit Obligation | Below are the actuarial weighted average assumptions used in determining the benefit obligation:
| 2017 |  |  | 2016 |
Discount rate | 3.75 | % |  | 4.00 | %
Rate of compensation increase(1) | — | % |  | — | %
(1)Rate of compensation increase is not applicable for 2017 and 2016 due to the amendment to freeze benefit accruals under the qualified and nonqualified defined benefit pension plans effective March 31, 2016.
Components of Net Periodic Pension Cost and Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) | The following table summarizes the components of net periodic pension cost and other changes in Plan assets and benefit obligations recognized in other comprehensive income (loss) for the years ended December 31:
(dollars in thousands) | 2017 |  |  | 2016 |  |  | 2015 |
Components of Net Periodic Pension Cost |  |  |  |  |
Service cost—benefits earned during the period | $ | — |  |  | $ | 463 |  |  | $ | 2,601 |
Interest cost on projected benefit obligation | 4,100 |  |  | 4,296 |  |  | 4,425 |
Expected return on plan assets | (6,313 | ) |  | (5,780 | ) |  | (7,180 | )
Amortization of prior service credit | — |  |  | (11 | ) |  | (138 | )
Recognized net actuarial loss | 1,866 |  |  | 2,345 |  |  | 2,028 |
Curtailment gain | — |  |  | (1,017 | ) |  | — |
Net Periodic Pension Expense | $ | (347 | ) |  | $ | 296 |  |  | $ | 1,736 |
Other Changes in Plan Assets and Benefit Obligation Recognized in Other Comprehensive Income (Loss) |  |  |  |  |
Net actuarial (gain) loss | $ | 3,678 |  |  | $ | (6,018 | ) |  | $ | 5,678 |
Recognized net actuarial loss | (1,866 | ) |  | (2,345 | ) |  | (2,028 | )
Recognized prior service credit | — |  |  | 1,029 |  |  | 138 |
Total (Before Tax Effects) | $ | 1,812 |  |  | $ | (7,334 | ) |  | $ | 3,788 |
Total Recognized in Net Benefit Cost and Other Comprehensive (Loss)/Income (Before Tax Effects) | $ | 1,465 |  |  | $ | (7,038 | ) |  | $ | 5,524 |
Actuarial Weighted Average Assumptions Used in Determining Net Periodic Pension Cost | The following table summarizes the actuarial weighted average assumptions used in determining net periodic pension cost:
| 2017 |  |  | 2016 |  |  | 2015 |
Discount rate | 4.00 | % |  | 4.25 | % |  | 4.00 | %
Rate of compensation increase(1) | — | % |  | 3.00 | % |  | 3.00 | %
Expected return on assets | 7.50 | % |  | 7.50 | % |  | 8.00 | %
1)Rate of compensation increase is not applicable for 2017 and 2016 due to the amendment to freeze benefit accruals under the qualified and nonqualified defined benefit pension plans effective March 31, 2016.
Estimated Future Benefit Payments | The following table provides information regarding estimated future benefit payments to be paid in each of the next five years and in the aggregate for the five years thereafter:
(dollars in thousands) | Amount |
2018 | $ | 7,175 |
2019 | 7,090 |
2020 | 6,956 |
2021 | 7,157 |
2022 | 7,106 |
2023 - 2027 | 32,658 |
Pension Plan Assets Measured at Fair Value on Recurring Basis | The following tables present our Plan assets measured at fair value on a recurring basis by fair value hierarchy level at December 31, 2017 and 2016. There were no transfers between Level 1 and Level 2 for items of a recurring basis during the periods presented. There were no purchases or transfers of Level 3 plan assets in 2017.
| December 31, 2017
| Fair Value Asset Classes(1)
(dollars in thousands) | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |
Cash and cash equivalents(2) | $ | — |  |  | $ | 1,780 |  |  | $ | — |  |  | $ | 1,780 |
Fixed income(3) | 27,738 |  |  | — |  |  | — |  |  | 27,738 |
Equities: |  |  |  |  |  |  |
Equity index mutual funds—international(4) | 4,016 |  |  | — |  |  | — |  |  | 4,016 |
Domestic individual equities(5) | 53,540 |  |  | — |  |  | — |  |  | 53,540 |
Total Assets at Fair Value | $ | 85,294 |  |  | $ | 1,780 |  |  | $ | — |  |  | $ | 87,074 |
(1)Refer to Note 1 Summary of Significant Accounting Policies, Fair Value Measurements for a description of levels within the fair value hierarchy. (2)This asset class includes FDIC insured money market instruments. (3)This asset class includes a variety of fixed income mutual funds which primarily invest in investment grade rated securities. Investment managers have discretion to invest in fixed income related securities including futures, options and other derivatives. Investments may be made in currencies other than the U.S. dollar. (4)The sole investment within this asset class is the Harbor International Institutional Fund. (5)This asset class includes individual domestic equities invested in an active all-cap strategy. It may also include convertible bonds.
| December 31, 2016
| Fair Value Asset Classes(1)
(dollars in thousands) | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Total |
Cash and cash equivalents(2) | $ | — |  |  | $ | 3,336 |  |  | $ | — |  |  | $ | 3,336 |
Fixed income(3) | 27,279 |  |  | — |  |  | — |  |  | 27,279 |
Equities: |  |  |  |  |  |  |
Equity index mutual funds—international(4) | 3,362 |  |  | — |  |  | — |  |  | 3,362 |
Domestic individual equities(5) | 53,636 |  |  | — |  |  | — |  |  | 53,636 |
Total Assets at Fair Value | $ | 84,277 |  |  | $ | 3,336 |  |  | $ | — |  |  | $ | 87,613 |
(1)Refer to Note 1 Summary of Significant Accounting Policies, Fair Value Measurements for a description of levels within the fair value hierarchy. (2)This asset class includes FDIC insured money market instruments. (3)This asset class includes a variety of fixed income mutual funds which primarily invest in investment grade rated securities. Investment managers have discretion to invest in fixed income related securities including futures, options and other derivatives. Investments may be made in currencies other than the U.S. dollar. (4)The sole investment within this asset class is MSCI EAFE Index iShares. (5)This asset class includes individual domestic equities invested in an active all-cap strategy. It may also include convertible bonds.

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