Unrecognized Tax Benefits Excluding Interest Correlative Effects and Indirect Benefits (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2014
Reconciliation of Unrecognized Tax Benefits
Unrecognized tax benefits at beginning of period	$ 11,826
Gross increases - tax positions in prior years	1,898
Gross decreases - tax positions in prior years	(204)
Gross increases - tax positions in current year	1,418
Gross increases as a result of lapse of statute of limitations	4,442
Gross decreases as a result of lapse of statute of limitations	(6,314)
Increases - uncertain tax positions assumed in connection with an acquisition	5,963
Unrecognized tax benefits at end of period	$ 19,029

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Unrecognized Tax Benefits, Increases Resulting from Lapse of Applicable Statute of Limitations

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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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 increase in unrecognized tax benefits resulting from acquisitions.

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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.

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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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