Taxes On Income (Reconciliation from the Expected Tax Expense (Benefit) Using the U.S. Federal Income Tax Rate) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Taxes On Income [Abstract]
Computed tax (benefit) expense at statutory rates	$ 9,124	$ (39,183)	$ 7,387
Increase (decrease) in income taxes results from:
Benefit of income not subject to U.S. Federal income tax	(213)	(165)	(135)
Expenses not deductible for U.S. Federal income tax	150	124	2,150
State income taxes, net of Federal income tax benefit	476	(3,755)	286
Reversal of FIN 48 reserve		(953)
Texas tax refund (federally tax affected)	50		(559)
Other	296	275	609
Taxes on income	$ 9,883	$ (43,657)	$ 9,738

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Reversal of FIN 48 Reserve resulting in a difference between the expected tax rate and the effective tax rate.

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- Definition

Texas Tax Refund (Federally Tax Affected) resulting in a difference between the expected tax rate and teh effective tax rate.

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No definition available.

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The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to pretax Income or Loss from continuing operations; income tax expense or benefit may include interest and penalties on tax uncertainties based on the entity's accounting policy.

+ References

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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The sum of the differences between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to nondeductible expenses under enacted tax laws, or differences in the methodologies used to determine expense amounts for financial statements prepared in accordance with generally accepted accounting principles and enacted tax laws.

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The sum of other amounts reflected in the reconciliation of the statutory tax provision (benefit) to the actual tax provision (benefit).

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The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations, that is attributable to state and local income tax expense or benefit.

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement for the period and the expected income tax expense or benefit computed by applying the domestic federal statutory income tax rates to pretax income from continuing operations attributable to income that is exempt from income taxes under enacted tax laws.

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