Investments (Schedule Of Available-For-Sale Securities Investments Results)(Details) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale equity securities, amortized cost	$ 7,790,000	$ 8,260,000
Available-for-sales securities, gross unrealized gains	14,810,000	16,500,000
Available-for-sale securities, gross unrealized losses	130,000	0
Avaialble-for-sale securities gross, Fair Value	22,470,000	24,760,000
Total gross unrealized gains, net of losses	14,680,000	16,500,000
Less: Deferred taxes on unrealized holdings gains	5,872,000	6,600,000
Unrealized gains recorded in equity, net of deferred tax	8,808,000	9,900,000
Cement Industry [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale equity securities, amortized cost	2,940,000	4,190,000
Available-for-sales securities, gross unrealized gains	9,100,000	8,290,000
Available-for-sale securities, gross unrealized losses	0	0
Avaialble-for-sale securities gross, Fair Value	12,040,000	12,480,000
General Building Materials Industry [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale equity securities, amortized cost	3,600,000	3,600,000
Available-for-sales securities, gross unrealized gains	2,120,000	2,150,000
Available-for-sale securities, gross unrealized losses	0	0
Avaialble-for-sale securities gross, Fair Value	5,720,000	5,750,000
Oil And Gas Refining And Marketing Industry [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale equity securities, amortized cost	340,000	470,000
Available-for-sales securities, gross unrealized gains	3,590,000	6,060,000
Available-for-sale securities, gross unrealized losses	0	0
Avaialble-for-sale securities gross, Fair Value	3,930,000	6,530,000
Residential Construction Industry [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale equity securities, amortized cost	910,000
Available-for-sales securities, gross unrealized gains	0
Available-for-sale securities, gross unrealized losses	130,000
Avaialble-for-sale securities gross, Fair Value	$ 780,000

Available For Sale Securities Change In Net Unrealized Gain Loss Net Of Tax

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Available For Sale Securities Gross Fair Value

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on trading securities.

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