Income Taxes (Reconciliation of Statutory Rate to Effective Tax Rate) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 01, 2012
Continuing operations:
Provisions using statutory federal income tax rate			$ 53,239	$ 29,801	$ 35,147
State income taxes, net of federal tax benefit			2,510	1,104	4,291
REIT Benefit			(44,538)	(34,454)	0
Impact of REIT election			0	(14,946)	(79,033)
Change in contingent tax liabilities			(576)	(5,701)	0
Reenactment of Federal Tax Credits			0	(1,084)	0
Other, net			3,458	(770)	(967)
Total provision (benefit) for income taxes from continuing operations			14,093us-gaap_IncomeTaxExpenseBenefit	(26,050)us-gaap_IncomeTaxExpenseBenefit	(40,562)us-gaap_IncomeTaxExpenseBenefit
Discontinued operations:
Tax benefit from operations of discontinued business	0	0	0	0	(7,805)	7,805
Total provision (benefit) for income taxes			$ 14,093	$ (26,050)	$ (48,367)

Effective Income Tax Reconciliation, REIT Benefit

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Income Tax Reconciliation, Impact Of REIT Election

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Tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items. Includes the tax effects of the following: income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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

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The sum of current income tax expense or benefit and deferred income tax expense or benefit pertaining to continuing operations, tax effect allocated to a disposal group that is classified as a component of the entity reported as a separate component of income before extraordinary items, and tax effect of gains and losses from events or transactions meeting the criteria to be classified as an extraordinary item.

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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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Amount 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 tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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