Unrecognized Tax Benefits Excluding Interest Correlative Effects and Indirect Benefits (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Reconciliation of Unrecognized Tax Benefits
Unrecognized tax benefits at beginning of period	$ 9,288
Gross increases - tax positions in prior years	19,527
Gross decreases - tax positions in prior years	(13,876)
Gross increases - tax positions in current year	1,409
Settlements with taxing authorities	(555)
Unrecognized tax benefits at end of period	$ 15,793

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

+ References

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

-Publisher FASB

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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

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The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

+ References

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

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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