Income Taxes (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]
Utility Plant Related	$ 39,020	$ 35,135
Customer Advances	(3,673)	(3,737)
Employee Benefits	6,523	6,342
Investment Tax Credits (ITC)	1,068	1,146
Other	(94)	(718)
Total Deferred Tax Liability and ITC	$ 42,844	$ 38,168

Amount of deferred tax liability attributable to taxable temporary differences from customer advances.

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Amount of deferred tax liability attributable to taxable temporary differences from Investment tax credits.

+ References

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Amount of deferred tax liability attributable to taxable temporary differences from Utility plant related.

+ References

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Amount of deferred tax liability attributable to taxable temporary differences net of deferred tax asset attributable to deductible temporary differences and carryforwards after valuation allowances.

+ References

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

-Publisher FASB

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Amount of deferred tax liability attributable to taxable temporary differences not separately disclosed.

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The amount as of the balance sheet date of the estimated future tax effects attributable to the difference between the tax basis of pension liabilities funded in advance and the basis of a prepaid pension asset determined in accordance with generally accepted accounting principles. The difference in basis of such costs will increase future taxable income when such basis difference reverses. Prepaid pension costs represented the cumulative employer's contributions in excess of net pension cost recognized, before the adoption of the recognition provisions of FAS 158. Under FAS 158, prepaid pension costs are no longer recognized in the statement of financial position.

+ References

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