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BENEFIT PLANS: (Tables) | 12 Months Ended
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Dec. 31, 2011
Peru Defined Benefit Pension Plans |
Components of net periodic benefit costs |
Schedule of components of net periodic benefit costs |
|  | Years ended December 31, |
(in millions) |  | 2011 |  | 2010 |  | 2009 |
Interest cost |  | $ | 0.6 |  | $ | 0.6 |  | $ | 0.7 |
Expected return on plan assets |  | (0.7 | ) | (0.7 | ) | (0.6 | )
Amortization of net loss |  | 0.1 |  | 0.1 |  | 0.1 |
Net periodic benefit cost |  | $ | — |  | $ | — |  | $ | 0.2 |
Schedule of changes in the benefit obligation and plan assets, the funded status of the plans and the amount recognized in balance sheet and accumulated other comprehensive income |
|  | As of December 31, |
(in millions) |  | 2011 |  | 2010 |
Change in benefit obligation: |  |  |  |  |
Projected benefit obligation at beginning of year |  | $ | 12.5 |  | $ | 12.1 |
Interest cost |  | 0.6 |  | 0.6 |
Benefits paid |  | (1.0 | ) | (0.9 | )
Actuarial gain census |  | 0.2 |  | 0.1 |
Actuarial gain assumption changes |  | 1.3 |  | 0.6 |
Projected benefit obligation at end of year |  | $ | 13.6 |  | $ | 12.5 |
Change in plan assets: |  |  |  |  |
Fair value of plan assets at beginning of year |  | $ | 16.6 |  | $ | 16.5 |
Actual return on plan assets |  | 1.1 |  | 1.0 |
Benefits paid |  | (0.9 | ) | (0.9 | )
Fair value of plan assets at end of year |  | $ | 16.8 |  | $ | 16.6 |
Funded status at end of year: |  | $ | 3.2 |  | $ | 4.1 |
ASC-715 amounts recognized in statement of financial position consists of: |  |  |  |  |
Non-current assets |  | $ | 3.2 |  | $ | 4.1 |
Current liabilities |  |  |  | — |
Non-current liabilities |  | — |  | — |
Total |  | $ | 3.2 |  | $ | 4.1 |
ASC-715 amounts recognized in accumulated other comprehensive income consists of: |  |  |  |  |
Net loss net of income tax |  | $ | 3.1 |  | $ | 2.5 |
Total (net of income tax of $1.7 million and $1.3 million in 2011 and 2010, respectively) |  | $ | 3.1 |  | $ | 2.5 |
Schedule of changes in accumulated other comprehensive income |
|  | As of December 31, |
(in millions) |  | 2011 |  | 2010 |
Reconciliation of accumulated other comprehensive income: |  |  |  |  |
Accumulated other comprehensive income at beginning of plan year |  | $ | 2.5 |  | $ | 2.3 |
Net loss/(gain)amortized during the year |  | (0.1 | ) | (* | )
Net loss/(gain)occurring during the year |  | 0.7 |  | 0.2 |
Net adjustment to accumulated other comprehensive income |  | 0.6 |  | 0.2 |
Accumulated other comprehensive income at end of plan year |  | $ | 3.1 |  | $ | 2.5 |
Summary of the amounts in accumulative other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of tax |
|  | As of December 31, |
(in millions) |  | 2011 |  | 2010 |
Net loss / (gain) |  | $ | 0.7 |  | $ | 0.2 |
Amortization of net (loss) gain |  | (0.1 | ) | (* | )
Total amortization expenses |  | $ | 0.6 |  | $ | 0.2 |
Schedule of assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost |
|  | 2011 |  | 2010 |  | 2009 |
Discount rate |  | 3.95 | % | 5.00 | % | 5.55 | %
Expected long-term rate of return on plan asset |  | 4.50 | % | 4.50 | % | 4.50 | %
Rate of increase in future compensation level |  | N/A |  | N/A |  | N/A |
Scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter |
Years |  | Expected Benefit Payments |
|  | (in millions) |
2012 |  | 1.0 |
2013 |  | 0.9 |
2014 |  | 1.0 |
2015 |  | 0.9 |
2016 |  | 0.9 |
2017 to 2021 |  | 4.6 |
Total |  | $ | 9.3 |
Peru Post-retirement Health Care Plan |
Components of net periodic benefit costs |
Schedule of components of net periodic benefit costs |
|  | Years ended December 31, |
(in millions) |  | 2011 |  | 2010 |  | 2009 |
Service cost |  | $ | — |  | $ | — |  | $ | — |
Amortization of net loss / (gain) |  | (* | ) | (* | ) | (* | )
Amortization of prior service cost / (credit) |  | (* | ) | (* | ) | (* | )
Interest cost |  | 0.1 |  | 0.1 |  | 0.1 |
Net periodic benefit cost |  | $ | 0.1 |  | $ | 0.1 |  | $ | 0.1 |
(*)Less than $0.1 million
Schedule of changes in the benefit obligation and plan assets, the funded status of the plans and the amount recognized in balance sheet and accumulated other comprehensive income |
|  | As of December 31, |
(in millions) |  | 2011 |  | 2010 |
Change in benefit obligation: |  |  |  |  |
Benefit obligation at beginning of year |  | $ | 1.7 |  | $ | 2.0 |
Interest cost |  | 0.1 |  | 0.1 |
Actuarial loss / (gain) — claims cost |  | — |  | (0.3 | )
Benefits paid |  | (0.1 | ) | (0.2 | )
Actuarial (gain) loss |  | 0.2 |  | 0.1 |
Benefit obligation at end of year |  | $ | 1.9 |  | $ | 1.7 |
Change in plan assets: |  |  |  |  |
Fair value of plan assets at beginning of year |  | $ | — |  | $ | — |
Employer contributions |  | 0.1 |  | 0.1 |
Benefits paid |  | (0.1 | ) | (0.1 | )
Fair value of plan assets at end of year |  | $ | — |  | $ | — |
Funded status at end of year |  | $ | (1.9 | ) | $ | (1.7 | )
ASC 715 amounts recognized in statement of financial position consists of: |  |  |  |  |
Non-current assets |  | $ | — |  | $ | — |
Current liabilities |  | (0.1 | ) | (0.1 | )
Non-current liabilities |  | (1.8 | ) | (1.6 | )
Total |  | $ | (1.9 | ) | $ | (1.7 | )
ASC 715 amounts recognized in accumulated other comprehensive income consists of: |  |  |  |  |
Net loss (gain) |  | $ | 0.6 |  | $ | 0.5 |
Prior service cost (credit) |  | (0.1 | ) | (0.1 | )
Total (net of income tax) |  | $ | 0.5 |  | $ | 0.4 |
Schedule of changes in accumulated other comprehensive income |
(in millions) |  | 2011 |  | 2010 |
Reconciliation of accumulated other comprehensive income: |  |  |  |  |
Accumulated other comprehensive income at beginning of plan year |  | $ | 0.4 |  | $ | 0.5 |
Net loss /(gain) occurring during the year |  | 0.1 |  | (0.1 | )
Net loss/gain amortized during the year |  | (* | ) | (* | )
Net adjustment to accumulated other comprehensive income |  | 0.1 |  | (0.1 | )
Accumulated other comprehensive income at end of plan year |  | $ | 0.5 |  | $ | 0.4 |
(*) Less than $0.1 million
Summary of the amounts in accumulative other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of tax |
|  | For the year ended December 31, |
(in millions) |  | 2011 |  | 2010 |
Net loss (gain) |  | $ | (0.1 | ) | $ | 0.1 |
Amortization of prior service cost (credit) |  | (* | ) | (* | )
Amortization of net losses |  | (* | ) | (* | )
Total amortization expenses |  | $ | (0.1 | ) | $ | 0.1 |
Scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter |
Year |  | Expected Benefit Payments |
|  | (in millions) |
2012 |  | $ | 0.1 |
2013 |  | 0.1 |
2014 |  | 0.1 |
2015 |  | 0.1 |
2016 |  | 0.1 |
2017 to 2021 |  | 0.6 |
Total |  | $ | 1.1 |
Minera Mexico Defined Benefit Pension Plans |
Components of net periodic benefit costs |
Schedule of components of net periodic benefit costs |
|  | For the years ended December 31, |
(in millions) |  | 2011 |  | 2010 |  | 2009 |
Interest cost |  | $ | 0.6 |  | $ | 1.6 |  | $ | 1.5 |
Service cost |  | 0.9 |  | 2.1 |  | 1.8 |
Expected return on plan assets |  | (2.8 | ) | (3.0 | ) | (2.2 | )
Amortization of transition assets, net |  | (0.1 | ) | — |  | (0.1 | )
Amortization of net actuarial loss |  | (1.3 | ) | (1.0 | ) | (0.1 | )
Amortization of prior services cost |  | — |  | 0.2 |  | 0.2 |
Settlement/curtailment(*) |  | — |  | (19.0 | ) | — |
Net periodic benefit cost |  | $ | (2.7 | ) | $ | (19.1 | ) | $ | 1.1 |
Schedule of changes in the benefit obligation and plan assets, the funded status of the plans and the amount recognized in balance sheet and accumulated other comprehensive income |
(in millions) |  | 2011 |  | 2010 |
Change in benefit obligation: |  |  |  |  |
Projected benefit obligation at beginning of year |  | $ | 12.7 |  | $ | 32.5 |
Service cost |  | 0.9 |  | 2.1 |
Interest cost |  | 0.6 |  | 1.6 |
Actuarial (loss) gain, net |  | (0.4 | ) | (0.6 | )
Benefits paid |  | (0.9 | ) | (0.9 | )
Settlement/curtailment (*) |  | — |  | (23.7 | )
Inflation adjustment |  | (1.3 | ) | 1.7 |
Projected benefit obligation at end of year |  | $ | 11.6 |  | $ | 12.7 |
(*)Included in the 2010 settlement/curtailment amount is a payment of $11.9 million severance to Buenavista workers who accepted the Company’s buyout offer.
Change in plan assets: |  |  |  |  |
Fair value of plan assets at beginning of year |  | $ | 46.3 |  | $ | 38.8 |
Actual return on plan assets |  | (1.1 | ) | 6.9 |
Employer contribution |  | (0.5 | ) | (0.6 | )
Benefits paid |  | (0.2 | ) | (0.9 | )
Currency exchange rate adjustment |  | (5.4 | ) | 2.1 |
Fair value of plan assets at end of year |  | $ | 39.1 |  | $ | 46.3 |
Funded status at end of year: |  | $ | 27.5 |  | $ | 33.6 |
ASC 715 amounts recognized in statement of financial position consists of: |  |  |  |  |
Non-current assets |  | $ | 27.5 |  | $ | 33.6 |
Total |  | $ | 27.5 |  | $ | 33.6 |
ASC 715 amounts recognized in accumulated other comprehensive income consists of: |  |  |  |  |
Net loss (gain) |  | $ | (7.0 | ) | $ | (11.2 | )
Transition obligation (asset) |  | — |  | (0.1 | )
Total (net of income tax of $4.7 million and $7.6 million, respectively) |  | $ | (7.0 | ) | $ | (11.3 | )
Schedule of changes in accumulated other comprehensive income |
(in millions) |  | 2011 |  | 2010 |
Reconciliation of accumulated other comprehensive income: |  |  |  |  |
Accumulated other comprehensive income at beginning of plan year |  | $ | (11.3 | ) | $ | (6.1 | )
Prior services cost amortized during the year |  | — |  | (0.1 | )
Net loss/gain amortized during the year |  | 0.8 |  | 0.6 |
Net loss (gains) occurring during the year. |  | 2.2 |  | (2.7 | )
Settlement/curtailment |  | — |  | (2.8 | )
Currency exchange rate changes |  | 1.3 |  | (0.2 | )
Net adjustment to accumulated other comprehensive income |  | 4.3 |  | (5.2 | )
Accumulated other comprehensive income at end of plan year |  | $ | (7.0 | ) | $ | (11.3 | )
Summary of the amounts in accumulative other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of tax |
|  | For the year ended December 31, |
(in millions) |  | 2011 |  | 2010 |
Amortization of net losses |  | $ | 0.8 |  | $ | 0.6 |
Amortization of prior services cost |  | — |  | (0.1 | )
Total amortization expenses |  | $ | 0.8 |  | $ | 0.5 |
Schedule of assumptions used to determine the pension obligation and seniority premiums as of year-end and the net cost |
|  | 2011 |  | 2010 |  | 2009 |
Weighted average discount rate |  | 7.5 | % | 7.5 | % | 8.0 | %
Expected long-term rate of return on plan asset |  | 7.5 | % | 7.5 | % | 8.0 | %
Rate of increase in future compensation level |  | 4.5 | % | 4.0 | % | 0.0 | %
Scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter |
Years |  | Expected Benefit Payments |
|  | (in millions) |
2012 |  | $ | 7.3 |
2013 |  | 0.5 |
2014 |  | 0.5 |
2015 |  | 0.5 |
2016 |  | 0.5 |
2017 to 2021 |  | 3.4 |
Total |  | $ | 12.7 |
Schedule of asset mix of the investment portfolio |
|  | 2011 |  | 2010 |
Asset category: |  |  |  |  |
Equity securities |  | 74 | % | 71 | %
Treasury bills |  | 26 | % | 29 | %
|  | 100 | % | 100 | %
Minera Mexico Post-retirement health care plan |
Components of net periodic benefit costs |
Schedule of components of net periodic benefit costs |
|  | For the years ended December 31, |
(in millions) |  | 2011 |  | 2010 |  | 2009 |
Interest cost |  | $ | 3.2 |  | $ | 4.3 |  | $ | 4.3 |
Service cost |  | — |  | 0.4 |  | 0.4 |
Amortization of net loss (gain) |  | — |  | 0.1 |  | 0.5 |
Amortization of transition obligation |  | 1.3 |  | 1.5 |  | 1.5 |
Amortization of prior service cost |  | (10.0 | ) | — |  | — |
Net periodic post-retirement benefit costs |  | $ | (5.5 | ) | $ | 6.3 |  | $ | 6.7 |
Schedule of changes in the benefit obligation and plan assets, the funded status of the plans and the amount recognized in balance sheet and accumulated other comprehensive income |
(in millions) |  | 2011 |  | 2010 |
Change in benefit obligation: |  |  |  |  |
Projected benefit obligation at beginning of year |  | $ | 49.7 |  | $ | 53.0 |
Service cost |  | — |  | 0.4 |
Interest cost |  | 3.2 |  | 4.3 |
Amendments |  | (24.2 | ) |  |
Actuarial (loss) gain, net |  | (3.3 | ) | (11.1 | )
Benefits paid |  | (1.3 | ) | — |
Currency exchange rate adjustment |  | (5.7 | ) | 3.1 |
Projected benefit obligation at end of year |  | $ | 18.4 |  | $ | 49.7 |
Funded status |  | (18.4 | ) | (49.7 | )
ASC-715 amounts recognized in statement of financial position consists of: |  |  |  |  |
Non-current assets |  | $ | — |  | $ | — |
Current liabilities |  | — |  | — |
Non-current liabilities |  | (18.4 | ) | (49.7 | )
Total |  | $ | (18.4 | ) | $ | (49.7 | )
ASC-715 amounts recognized in accumulated other comprehensive income consists of: |  |  |  |  |
Net loss (gain) |  | $ | (4.0 | ) | $ | (2.3 | )
Prior service cost (credit) |  | — |  | — |
Transition obligation (asset) |  | — |  | 10.5 |
Total (net of income tax of $(2.7) million and $5.5 million, respectively) |  | $ | (4.0 | ) | $ | 8.2 |
Schedule of changes in accumulated other comprehensive income |
(in millions) |  | 2011 |  | 2010 |
Reconciliation of accumulated other comprehensive income: |  |  |  |  |
Accumulated other comprehensive income at beginning of plan year |  | $ | 8.2 |  | $ | 15.5 |
Amortization of net loss (gain) |  | — |  | (0.1 | )
Amortization of transition obligation |  | (0.8 | ) | (0.9 | )
Amortization of prior service cost (credit) |  | 6.0 |  | — |
Prior services cost (credit) |  | (14.5 | ) | — |
Net loss / (gain) occurring during the year. |  | (2.0 | ) | (6.7 | )
Currency exchange rate changes |  | (0.9 | ) | 0.4 |
Net adjustment to accumulated other comprehensive income |  | (12.2 | ) | (7.3 | )
Accumulated other comprehensive income at end of plan year |  | $ | (4.0 | ) | $ | 8.2 |
Summary of the amounts in accumulative other comprehensive income amortized and recognized as a component of net periodic benefit cost, net of tax |
|  | For the year ended December 31, |
(in millions) |  | 2011 |  | 2010 |
Amortization of transation obligation |  | $ | 0.8 |  | $ | 0.9 |
Amortization of prior service cost (credit) |  | (6.0 | ) | — |
Amortization of net losses |  | — |  | 0.1 |
Total amortization expenses |  | $ | (5.2 | ) | $ | 1.0 |
Scheduled maturities of the benefits expected to be paid in each of the next five years, and thereafter |
Years |  | Expected Benefit Payments |
|  | (in millions) |
2012 |  | $ | 1.4 |
2013 |  | 1.5 |
2014 |  | 1.6 |
2015 |  | 1.7 |
2016 |  | 1.8 |
2017 to 2021 |  | 13.0 |
Total |  | $ | 21.0 |
Schedule of effects of one percentage-point change in assumed other benefits cost trend rates |
|  | One Percentage Point |
(in millions) |  | Increase |  | Decrease |
Effect on total service and interest cost components |  | $ | 1.5 |  | $ | 1.2 |
Effect on the post-retirement benefit obligation |  | $ | 20.2 |  | $ | 16.8 |

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- Definition Tabular disclosure of the change in the benefit obligation and fair value of the assets of pension plans from the beginning to the end of the period, showing separately, if applicable, the effects of the following: service cost, interest cost, contributions by plan participants, actuarial gains and losses, foreign currency exchange rate changes, benefits paid, plan amendments, business combinations, divestitures, curtailments, settlements, and special and contractual termination benefits. This also includes amount recognized in balance sheet and accumulated other comprehensive income. + References No definition available. + Details
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- Definition Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Topic 715 -SubTopic 20 -Publisher FASB -Number -Article -Subparagraph (d)(5) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920 + Details
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