Unrecognized Tax Benefits Excluding Interest Correlative Effects and Indirect Benefits (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Reconciliation of Unrecognized Tax Benefits
Unrecognized tax benefits at beginning of period	$ 15,380
Gross increases - tax positions in prior years	4,520
Gross decreases - tax positions in prior years	(4,336)
Gross increases - tax positions in current year	1,176
Settlements with taxing authorities	(8,599)
Lapse of statute of limitations	(1,691)
Unrecognized tax benefits at end of period	$ 6,450

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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