Retirement Plans (Asset Allocation Policy Ranges) (Details)	12 Months Ended
Dec. 31, 2011
Retirement Plans [Abstract]
Equities - Minimum	25.00%
Equities - Maximum	75.00%
Fixed income - Minimum	10.00%
Fixed income - Maximum	50.00%
Cash - Minimum	0.00%
Cash - Maximum	15.00%
Other asset classes - Minimum	0.00%
Other asset classes - Maximum	20.00%

Defined Benefit Plan Target Allocation Percentage Of Assets Cash Range Maximum

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- Definition

Defined Benefit Plan Target Allocation Percentage Of Assets Cash Range Minimum

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- Definition

Defined Benefit Plan Target Allocation Percentage Of Assets Fixed Income Securities Range Maximum

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No definition available.

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- Definition

Defined Benefit Plan Target Allocation Percentage Of Assets Fixed Income Securities Range Minimum

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No definition available.

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- Definition

Target allocation maximum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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- Definition

Target allocation minimum percentage of investments in equity securities to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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Target allocation maximum percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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- Definition

Target allocation minimum percentage in other than debt securities, equity securities, and real estate to total plan assets presented on a weighted-average basis as of the measurement date of the latest statement of financial position.

+ References

No definition available.

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