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Employee Retirement Plans (Tables) | 12 Months Ended
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Dec. 31, 2016
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract] |
Schedule of Funded Status | The following table presents the changes in the plan’s projected benefit obligation, fair value of plan assets, and funded status for the years ended December 31 (in thousands):
| 2016 |  | 2015 |  | 2014
Projected benefit obligation at January 1 | $ | 1,685 |  |  | $ | 1,961 |  |  | $ | 2,179 |
Interest cost | 59 |  |  | 66 |  |  | 88 |
Actuarial losses (gains) | 5 |  |  | (39 | ) |  | 9 |
Benefits paid | (372 | ) |  | (303 | ) |  | (315 | )
Projected benefit obligation at December 31 | 1,377 |  |  | 1,685 |  |  | 1,961 |
Fair value of plan assets | — |  |  | — |  |  | — |
Under funded status | (1,377 | ) |  | (1,685 | ) |  | (1,961 | )
Unamortized prior service cost | 4 |  |  | 10 |  |  | 24 |
Unrecognized actuarial gain | (200 | ) |  | (218 | ) |  | (179 | )
Net amount recognized | $ | (1,573 | ) |  | $ | (1,893 | ) |  | $ | (2,116 | )
Schedule of Defined Benefit Plan, Amounts Recognized in Consolidated Financial Statements | Amounts recognized in the consolidated financial statements consisted of (in thousands):
Accrued pension liability: |  |  |  |  |
Current portion | $ | (360 | ) |  | $ | (372 | ) |  | $ | (395 | )
Long term portion | (1,016 | ) |  | (1,313 | ) |  | (1,566 | )
Pre-tax accumulated other comprehensive income – retirement benefit liability adjustment | (197 | ) |  | (208 | ) |  | (155 | )
Net amount recognized | $ | (1,573 | ) |  | $ | (1,893 | ) |  | $ | (2,116 | )
Components of Net Periodic Pension and Other Post-Retirement Benefit Costs Charged to Expense | Components of net periodic pension cost for the years ended December 31 were as follows (in thousands):
| 2016 |  | 2015 |  | 2014
Interest cost | $ | 59 |  |  | $ | 66 |  |  | $ | 88 |
Amortization of unrecognized prior service cost | 6 |  |  | 14 |  |  | 15 |
Gain amortization | (13 | ) |  | — |  |  | — |
Net periodic pension cost | $ | 52 |  |  | $ | 80 |  |  | $ | 103 |
Assumptions used to calculate the benefit obligation: |  |  |  |  |
Discount rate | 3.81 | % |  | 3.94 | % |  | 3.74 | %
Schedule of Expected Benefit Payments | Expected benefit payments from the plan for the years ended December 31 are as follows (in thousands):
2017 | $ | 360 |
2018 | $ | 327 |
2019 | $ | 228 |
2020 | $ | 137 |
2021 | $ | 100 |
Years 2022 - 2026 | $ | 392 |
Schedule of Multiemployer Plans | The Company’s participation in these plans for the year ended December 31, 2016 is outlined in the table below. The “EIN/ Pension Plan Number” column provides the Employee Identification Number (EIN) and three-digit plan number, if applicable. Unless otherwise noted, the most recent Pension Protection Act (PPA) zone status available in 2016 and 2015 is for the plan’s year ended December 31, 2015 and 2014, respectively. The zone status is based on information that the Company received from the plans and is certified by the plans’ actuaries. Among other factors, plans in the red zone are generally less than 65% funded, plans in the yellow zone are less than 80% funded, and plans in the green zone are at least 80% funded.
| EIN/ Pension |  | PPA Zone Status |  | Surcharge
Pension Fund | Plan Number |  | 2015 |  | 2014 |  | Imposed
National Integrated Group Pension Plan | 22-6190618-001 |  | Red |  | Red |  | Yes
Sheet Metal Workers’ National Pension Plan | 52-6112463-001 |  | Yellow |  | Yellow |  | Yes
Sheet Metal Workers’ Pension Plan of Northern California | 51-6115939-001 |  | Red |  | Red |  | No
Schedule of Contributions Made by the Company to Each Multiemployer Plan | The table below sets forth the contributions made by the Company to each multiemployer plan for the years ended December 31 (in thousands):
Pension Fund | 2016 |  | 2015 |  | 2014
National Integrated Group Pension Plan | $ | 218 |  |  | $ | 246 |  |  | $ | 233 |
Sheet Metal Workers’ National Pension Plan | 50 |  |  | 56 |  |  | 61 |
Sheet Metal Workers’ Pension Plan of Northern California | 28 |  |  | 31 |  |  | 35 |
| $ | 296 |  |  | $ | 333 |  |  | $ | 329 |
Schedule of Total Expense for All Retirement Plans | Total expense for all retirement plans for the years ended December 31 was (in thousands):
2016 |  | 2015 |  | 2014
$ | 2,887 |  |  | $ | 2,934 |  |  | $ | 2,816 |

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