Unrecognized Tax Benefits Excluding Interest and Correlative Effects (Detail) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Jun. 30, 2012
Reconciliation of Unrecognized Tax Benefits
Unrecognized tax benefits at beginning of period	$ 9,288
Gross increases - tax positions in prior years	9,366
Gross decreases - tax positions in prior years	(13,876)
Gross increases - tax positions in current year	905
Settlements with taxing authorities	(555)
Unrecognized tax benefits at end of period	$ 5,128

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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.

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-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

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

+ References

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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

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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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