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Reconciliation of Beginning and Ending Balances for Plan Assets Valued using Significant Unobservable Inputs (Detail) (USD $)
In Millions, unless otherwise specified |
12 Months Ended |
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Dec. 31, 2011
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Private Equity
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| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |
| Beginning balance | $ 31.8 |
| Return on plan assets: | |
| Unrealized | 3.2 |
| Purchases | 4.1 |
| Sales | (6.1) |
| Level 3 transfers, net | |
| Ending balance | 33.0 |
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Hedge Funds
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| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |
| Beginning balance | 93.2 |
| Return on plan assets: | |
| Unrealized | (4.7) |
| Realized | 0.1 |
| Purchases | 8.7 |
| Sales | (4.4) |
| Level 3 transfers, net | |
| Ending balance | 92.9 |
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Real Assets
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| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | |
| Beginning balance | 8.0 |
| Return on plan assets: | |
| Unrealized | 0.9 |
| Realized | 0.3 |
| Purchases | 0.9 |
| Sales | (0.3) |
| Level 3 transfers, net | |
| Ending balance | $ 9.8 |
| X | ||||||||||
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- Definition
Defined Benefit Plan Assets With Unobservable Inputs No definition available.
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- Definition
Defined Benefit Plan Assets With Unobservable Inputs Purchases No definition available.
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- Definition
Defined Benefit Plan Assets With Unobservable Inputs Realized Gain Loss No definition available.
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- Definition
Defined Benefit Plan Assets With Unobservable Inputs Sales No definition available.
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- Definition
Defined Benefit Plan Assets with Unobservable Inputs, Unrealized Gain No definition available.
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- Details
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- Definition
Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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