CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Comprehensive income:
Net income	$ 658,683us-gaap_ProfitLoss	$ 1,905,353us-gaap_ProfitLoss	$ 881,204us-gaap_ProfitLoss
Other comprehensive (loss) income - derivative instruments:
Unrealized holding (losses) gains arising during the year	(33,306)	18,771	(11,772)
Losses reclassified into earnings from other comprehensive income	(16,868)	(20,141)	(14,678)
Other comprehensive income (loss) - other instruments:
Unrealized holding gains arising during the year	0	583	664
(Gains) realized during the year	0us-gaap_GainLossOnSaleOfSecuritiesNet	(2,122)us-gaap_GainLossOnSaleOfSecuritiesNet	0us-gaap_GainLossOnSaleOfSecuritiesNet
Other comprehensive (loss) income – foreign currency:
Currency translation adjustments arising during the year	(552)	613	0
Other comprehensive (loss) income	(16,990)	37,986	3,570
Comprehensive income	641,693	1,943,339	884,774
Comprehensive (income) attributable to Noncontrolling Interests	(26,728)	(76,204)	(39,624)
Comprehensive income attributable to controlling interests	$ 614,965us-gaap_ComprehensiveIncomeNetOfTax	$ 1,867,135us-gaap_ComprehensiveIncomeNetOfTax	$ 845,150us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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