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Income Taxes (Reconciliation Of The Statutory U.S. Federal Income Tax Rate Of 35% To The Company’s Effective Tax Rate) (Details)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
U.S. Statutory Tax Rate	35.00%	35.00%	35.00%
Less: rate attributable to noncontrolling interests	(26.50%)	(28.20%)	(28.20%)
State, local and foreign taxes, net of federal benefit	2.10%	1.30%	2.60%
Subtotal	10.60%	8.10%	9.40%
Effects of the Tax Act	13.70%	0.00%	0.00%
Effective income tax rate	24.30%	8.10%	9.40%

X

- Definition

The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate that can be explained by the state, local and foreign income tax expense or benefit, net of the federal tax benefit (expense) thereon, recorded during the period.

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- Definition

Effective Income Tax Rate Reconciliation, Total Before Change in Enacted Tax Rate, Percent

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the income tax rates.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to noncontrolling interest income (loss) exempt from income taxes.

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