CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 67,303us-gaap_ProfitLoss	$ 53,971us-gaap_ProfitLoss
Other comprehensive income (loss):
Unrealized gain (loss) on interest rate swap agreements	(6,203)	(895)
Other comprehensive income (loss)	(6,203)	(895)
Comprehensive income	61,100	53,076
Net income attributable to noncontrolling interest	(9,945)	(8,180)
Other comprehensive (income) loss attributable to noncontrolling interest	917	136
Comprehensive income attributable to common stockholders	$ 52,072us-gaap_ComprehensiveIncomeNetOfTax	$ 45,032us-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 of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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

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Amount after tax of other comprehensive income (loss) attributable to noncontrolling interests.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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