Income Taxes (Schedule of Effective Income Tax Rate Reconciliation) (Details) (USD $)	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Line Items]
Statutory rate	34.00%	34.00%	34.00%
Threshold amount	$ 10,000,000	$ 10,000,000	$ 10,000,000
Computed at statutory rate	3,694,000	4,820,000	1,612,000
State income taxes, net of federal tax benefit (expense)	155,000	195,000	(90,000)
Percentage depletion	(494,000)	(794,000)	(271,000)
Valuation allowance	0	(399,000)	15,000
Domestic production activities deduction	0	0	(28,000)
Dividends received deduction	(400,000)	(17,000)	(40,000)
Other	(85,000)	(80,000)	42,000
Provision for income taxes	$ 2,870,000	$ 3,725,000	$ 1,240,000
Statutory Rate Over $10 Million [Member]
Income Tax Disclosure [Line Items]
Statutory rate	35.00%	35.00%	35.00%

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Income tax reconciliation statutory rate threshold amount

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- Definition

The domestic federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate is the regular tax rate if there are alternative tax systems.

+ References

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-Subparagraph (SAB TOPIC 6.I)

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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-Section S99

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-Subparagraph (SX 210.4-08.(h))

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-Glossary Income Tax Expense (or Benefit)

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-Subparagraph (a),(b)

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The portion of the difference between total income tax expense or benefit as reported in the Income Statement 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 changes in the valuation allowance for deferred tax assets in the period.

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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 the deduction for dividends paid or received under enacted tax laws.

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- Definition

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 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 the different methods of depletion allowed under generally accepted accounting principles and enacted tax laws.

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- Definition

The portion of the difference, between total income tax expense or benefit as reported in the Income Statement for the year/accounting 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 all other items not otherwise listed in the existing taxonomy.

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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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