Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2014	Mar. 31, 2013
Condensed Consolidated Statements of Comprehensive Income
Net income	$ 41,209	$ 33,931
Other comprehensive income (loss):
Change in fair value of interest rate swaps	(2,747)	1,571
Total comprehensive income	38,462	35,502
Less: comprehensive income attributable to noncontrolling interests	3,750	2,563
Comprehensive income attributable to common stockholders	$ 34,712	$ 32,939

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 of (increase) decrease in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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

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