CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Comprehensive income:
Net income	$ 190,224us-gaap_ProfitLoss	$ 82,732us-gaap_ProfitLoss
Other comprehensive (loss) income – derivative instruments:
Unrealized holding (losses) arising during the period	(11,788)	(11,952)
Losses reclassified into earnings from other comprehensive income	4,338	4,129
Other comprehensive (loss) income – foreign currency:
Currency translation adjustments arising during the period	(420)	91
Other comprehensive (loss)	(7,870)	(7,732)
Comprehensive income	182,354	75,000
Comprehensive (income) attributable to Noncontrolling Interests	(7,402)	(3,302)
Comprehensive income attributable to controlling interests	$ 174,952us-gaap_ComprehensiveIncomeNetOfTax	$ 71,698us-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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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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