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Fair Value Measurements of Investments Held by Retirement Plan (Parenthetical) (Detail) - Common/Collective Trusts - Equity - Large-Cap Value	Dec. 31, 2015 Stock
Minimum
Defined Benefit Plan Disclosure [Line Items]
Number of stocks held	60
Maximum
Defined Benefit Plan Disclosure [Line Items]
Number of stocks held	70

X

- Definition

Number of Stocks

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Details

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Balance Type:
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X

- Details

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X

- Details

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X

- Details

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