Taxes on Income (Schedule of Unrecognized Tax Benefits) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Unrecognized Tax Benefits [Line Items]
Unrecognized tax benefits at January 1	$ 88	$ 967
Tax positions taken during prior years	(3)	96
Tax positions taken during current year
Reductions relating to settlements with taxing authorities	(85)
Reductions as a result of a lapse of statutes of limitations		(975)
Unrecognized tax benefits at December 31		$ 88

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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

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

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- Definition

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 decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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

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Unrecognized Tax Benefits Increases Decreases Resulting From Prior Period Tax Positions

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