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Pension and Other Postretirement Benefits (Tables) | 12 Months Ended
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Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract] |
Schedule of Changes in Projected Benefit Obligations | The change in benefit obligations and change in plan assets as of December 31 are as follows:
| Pension |  | OPEB
| 2014 | 2013 |  | 2014 | 2013
Change in benefit obligation: |  |  |  |  |
Benefit obligation at beginning of year | $ | 238,319 |  | $ | 174,954 |  |  | $ | 134,652 |  | $ | 149,263 |
Service cost | 5,605 |  | 4,735 |  |  | 1,591 |  | 2,527 |
Interest cost | 11,629 |  | 8,908 |  |  | 6,420 |  | 5,681 |
Plan amendments | (5,308 | ) | — |  |  | — |  | — |
Medicare Part D | — |  | — |  |  | 273 |  | — |
Actuarial loss (gain) | 32,772 |  | (21,539 | ) |  | 17,669 |  | (24,170 | )
Acquisition | 84,743 |  | 82,988 |  |  | 2,857 |  | 6,544 |
Benefits paid | (11,895 | ) | (11,727 | ) |  | (4,681 | ) | (5,193 | )
Settlements | (19,573 | ) | — |  |  | — |  | — |
Benefit obligation at end of year | $ | 336,292 |  | $ | 238,319 |  |  | $ | 158,781 |  | $ | 134,652 |
Schedule of Changes in Fair Value of Plan Assets |
| Pension |  | OPEB
| 2014 | 2013 |  | 2014 | 2013
Change in plan assets: |  |  |  |  |
Fair value of plan assets at beginning of year | $ | 199,304 |  | $ | 96,234 |  |  | $ | — |  | $ | — |
Actual return on plan assets | 16,118 |  | 21,675 |  |  | — |  | — |
Acquisition | 115,982 |  | 81,992 |  |  | — |  | — |
Employer contributions | 5,584 |  | 11,130 |  |  | 4,681 |  | 5,193 |
Benefits paid | (11,895 | ) | (11,727 | ) |  | (4,681 | ) | (5,193 | )
Settlements | (19,573 | ) | — |  |  | — |  | — |
Fair value of assets at end of year | $ | 305,520 |  | $ | 199,304 |  |  | $ | — |  | $ | — |
Schedule of Amounts Recognized in Balance Sheet |
| Pension |  | OPEB
| 2014 | 2013 |  | 2014 | 2013
Funded status of plans: |  |  |  |  |
Funded status | $ | (30,772 | ) | $ | (39,015 | ) |  | $ | (158,781 | ) | $ | (134,652 | )
Amounts recognized in the Consolidated Balance Sheets: |  |  |  |  |  |  |  |  |
Non-current assets | $ | 30,842 |  | $ | 2,547 |  |  | $ | — |  | $ | — |
Current liabilities | (1,744 | ) | (1,714 | ) |  | (6,118 | ) | (5,368 | )
Non-current liabilities | (59,870 | ) | (39,848 | ) |  | (152,663 | ) | (129,284 | )
Net amount recognized | $ | (30,772 | ) | $ | (39,015 | ) |  | $ | (158,781 | ) | $ | (134,652 | )
Amounts recognized in accumulated other comprehensive loss (pre-tax): |  |  |  |  |  |  |
Net loss | $ | 63,360 |  | $ | 45,642 |  |  | $ | 79,720 |  | $ | 65,754 |
Prior service cost (benefit) | 1,335 |  | 376 |  |  | (15,751 | ) | (19,595 | )
| $ | 64,695 |  | $ | 46,018 |  |  | $ | 63,969 |  | $ | 46,159 |
Schedule of Accumulated and Projected Benefit Obligations | Our pension plans’ projected benefit obligation, accumulated benefit obligation, and fair value of plan assets as of December 31 are as follows:
| Projected Benefit Obligation |  | Accumulated Benefit Obligation |  | Fair Value of Plan assets
| 2014 | 2013 |  | 2014 | 2013 |  | 2014 | 2013
Sebree hourly pension plan | $ | 90,320 |  | $ | 80,369 |  |  | $ | 90,320 |  | $ | 80,369 |  |  | $ | 84,432 |  | $ | 82,916 |
CAWV hourly pension plan | 61,989 |  | 66,866 |  |  | 61,989 |  | 66,852 |  |  | 55,273 |  | 64,905 |
Salaried pension plan | 71,017 |  | 66,686 |  |  | 68,247 |  | 60,870 |  |  | 49,367 |  | 51,483 |
CASC pension plan | 85,605 |  | — |  |  | 82,556 |  | — |  |  | 116,448 |  | — |
SERB plan | 27,361 |  | 24,398 |  |  | 25,851 |  | 23,369 |  |  | — |  | — |
Total | $ | 336,292 |  | $ | 238,319 |  |  | $ | 328,963 |  | $ | 231,460 |  |  | $ | 305,520 |  | $ | 199,304 |
Schedule of Net Benefit Cost | Net Periodic Benefit Cost:
| Year Ended December 31,
| Pension |  | OPEB
| 2014 | 2013 | 2012 |  | 2014 | 2013 | 2012
Service cost | $ | 5,605 |  | $ | 4,735 |  | $ | 2,802 |  |  | $ | 1,591 |  | $ | 2,527 |  | $ | 1,790 |
Interest cost | 11,629 |  | 8,908 |  | 6,871 |  |  | 6,420 |  | 5,681 |  | 5,512 |
Expected return on plan assets | (14,694 | ) | (10,592 | ) | (6,962 | ) |  | — |  | — |  | — |
Amortization of prior service costs | 77 |  | 113 |  | 137 |  |  | (3,844 | ) | (3,995 | ) | (4,250 | )
Amortization of net loss | 1,907 |  | 3,152 |  | 3,642 |  |  | 3,704 |  | 5,022 |  | 6,195 |
Net periodic benefit cost | 4,524 |  | 6,316 |  | 6,490 |  |  | 7,871 |  | 9,235 |  | 9,247 |
Settlements | 4,701 |  | — |  | — |  |  | — |  | — |  | — |
Curtailment cost | 263 |  | (18 | ) | — |  |  | — |  | (20 | ) | — |
Total net periodic benefit cost | $ | 9,488 |  | $ | 6,298 |  | $ | 6,490 |  |  | $ | 7,871 |  | $ | 9,215 |  | $ | 9,247 |
Schedule of Amounts Recognized in Other Comprehensive Income (Loss) | Other changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Loss (pre-tax):
| Year Ended December 31,
| Pension |  | OPEB
| 2014 | 2013 |  | 2014 | 2013
Net loss (gain) | $ | 24,326 |  | $ | (32,624 | ) |  | $ | 17,669 |  | $ | (24,171 | )
Prior service cost (benefit) | 1,299 |  | — |  |  | — |  | — |
Amortization of net loss, including recognition due to settlement | (6,608 | ) | (3,152 | ) |  | (3,704 | ) | (5,022 | )
Amortization of prior service benefit (cost), including recognition due to curtailment | (340 | ) | (95 | ) |  | 3,844 |  | 4,015 |
Total amount recognized in other comprehensive loss | 18,677 |  | (35,871 | ) |  | 17,809 |  | (25,178 | )
Net periodic benefit cost | 9,488 |  | 6,298 |  |  | 7,871 |  | 9,215 |
Total recognized in net periodic benefit cost and other comprehensive loss | $ | 28,165 |  | $ | (29,573 | ) |  | $ | 25,680 |  | $ | (15,963 | )
Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year |
Amounts in accumulated other comprehensive loss expected to be recognized as components of net periodic benefit cost during 2015:
| Pension |  | OPEB
Amortization of net loss | $ | 3,601 |  |  | $ | 4,712 |
Amortization of prior service cost (benefit) | 99 |  |  | (3,845 | )
Weighted average assumptions used in calculating benefit obligation and net periodic benefit cost | Weighted average assumptions used to determine benefit obligations at December 31:
| Pension |  | OPEB
| 2014 | 2013 |  | 2014 | 2013
Discount rate | 4.05% | 4.89% |  | 4.00% | 4.99%
Rate of compensation increase (1) | 3%/4% | 3%/4% |  | 3%/4% | 3%/4%
Measurement date | 12/31/2014 | 12/31/2013 |  | 12/31/2014 | 12/31/2013
(1) | The rate of compensation increase is 3% per year for first four years and 4% per year for year five and thereafter.
Weighted average assumptions used to determine net periodic benefit cost for the years ended December 31:
| Pension |  | OPEB
| 2014 | 2013 | 2012 |  | 2014 | 2013 | 2012
Measurement date | 12/31/2013 |  | 12/31/2012 |  | 12/31/2011 |  |  | 12/31/2013 |  | 12/31/2012 |  | 12/31/2011 |
Fiscal year end | 12/31/2014 |  | 12/31/2013 |  | 12/31/2012 |  |  | 12/31/2014 |  | 12/31/2013 |  | 12/31/2012 |
Discount rate | 4.89 | % | 4.00 | % | 4.25 | % |  | 4.99 | % | 4.01 | % | 3.83 | %
Rate of compensation increase (1) | 3%/4% |  | 3%/4% |  | 3%/4% |  |  | 3%/4% |  | 3%/4% |  | 3%/4% |
Expected return on plan assets | 7.25 | % | 7.25 | % | 8.00 | % |  | — |  | — |  | — |
(1) | For 2014, the rate of compensation increase is 3% per year for first four years and 4% per year for year five and thereafter. For 2013 and 2012, the rate of compensation increase is 3% per year for first five years and 4% per year for year six and thereafter.
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates | A one-percentage-point change in the assumed health care cost trend rate would have had the following effects in 2014:
| 1% Increase |  | 1% Decrease
Effect on total of service and interest cost | $ | 1,258 |  |  | $ | (1,019 | )
Effect on accumulated postretirement benefit obligation | 24,815 |  |  | (20,140 | )
Schedule of Matching Contribution to Defined Contribution Plans | Employee and matching contributions are considered fully vested immediately upon participation in the plan.
| 2014 | 2013 | 2012
Company matching contribution to defined contribution (401(k)) plans | $ | 1,547 |  | $ | 1,138 |  | $ | 748 |
Schedule of Allocation of Plan Assets | The Pension Plans’ long-term strategic asset allocation policy targets are as follows:
| Pension Plan Asset Allocation
| Policy Target | December 31, 2014 | December 31, 2013
Equities: |  |  |
U.S. equities | 50 | % | 42 | % | 43 | %
International equities | 15 | % | 18 | % | 20 | %
Fixed income | 35 | % | 40 | % | 37 | %
|  |  | 100 | % | 100 | %
Fair Value of Pension Plans’ assets included under the fair value hierarchy:
As of December 31, 2014 | Level 1 | Level 2 | Level 3 | Total
Equities: |  |  |  |
U.S. equities | $ | 79,148 |  | $ | — |  | $ | — |  | $ | 79,148 |
International equities | 33,720 |  | — |  | — |  | 33,720 |
Fixed income | 76,204 |  | — |  | — |  | 76,204 |
Plan receivable (1) | — |  | — |  | 116,448 |  | 116,448 |
Total | $ | 189,072 |  | $ | — |  | $ | 116,448 |  | $ | 305,520 |
As of December 31, 2013 |  |  |  |  |  |  |  |
Equities: |  |  |  |  |  |  |  |
U.S. equities | $ | 86,323 |  | $ | — |  | $ | — |  | $ | 86,323 |
International equities | 40,093 |  | — |  | — |  | 40,093 |
Fixed income | 72,888 |  | — |  | — |  | 72,888 |
Total | $ | 199,304 |  | $ | — |  | $ | — |  | $ | 199,304 |
(1) | Represents the receivable to the Century Aluminum of South Carolina defined benefit plan related to pension funding obligations under the Stock Purchase Agreement. Amount is subject to final approval by the parties which is expected in the second quarter of 2015.
Schedule Of Expected Benefit Plan Contributions | We expect to make the following contributions for 2015:
| 2015
Expected pension plan contributions | $ | 5,306 |
Expected OPEB benefits payments | 6,118 |
Schedule of Expected Benefit Payments | The following table provides the estimated future benefit payments for the pension and other postretirement benefit plans:
| Pension Benefits |  | OPEB Benefits
2015 | $ | 17,487 |  |  | $ | 6,118 |
2016 | 17,965 |  |  | 6,605 |
2017 | 18,191 |  |  | 7,212 |
2018 | 19,958 |  |  | 7,691 |
2019 | 19,830 |  |  | 8,216 |
2020 – 2024 | 97,247 |  |  | 43,357 |
Schedule of Multiemployer Plans | Century’s participation in the plan for the year ended December 31, 2014, is outlined in the table below.
Fund | Steelworkers Pension Trust
EIN / PN | 23-6648508/499
Pension Protection Act Zone Status 2014 (1) | Green
Pension Protection Act Zone Status 2013 (1) | Green
Subject to Financial Improvement/Rehabilitation Plan | No
Contributions of Century Aluminum 2014 | $2,164
Contributions of Century Aluminum 2013 | $2,171
Contributions of Century Aluminum 2012 | $2,282
Withdrawal from Plan Probable | No
Surcharge Imposed | No
Expiration Date of Collective Bargaining Agreement | April 1, 2015
(1) | The most recent Pension Protection Act zone status available in 2014 and 2013 is for the plan's year-end December 31, 2013 and December 31, 2012, respectively. The zone status is based on information that Century received from the plan as well as publicly available information per the Department of Labor and is certified by the plan’s actuary. Among other factors, plans in the green zone are at least 80 percent funded.

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