Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income attributable to the Company	$ 18,783us-gaap_NetIncomeLoss	$ 17,041us-gaap_NetIncomeLoss
Other comprehensive income/ (loss), net of tax [Abstract]
Unrealized gain/ (loss) on securities available for sale	2,331	1,125
Reclassification adjustment for net realized gain/ (loss) included in net income	5	1
Net unrealized gain/ (loss) on securities available for sale	2,326	1,124
Unrealized gain/ (loss) on cash flow hedges	(1,100)	(587)
Reclassification adjustment for net realized gain/ (loss) included in net income	(591)	(355)
Net change in unrealized gain/ (loss) on cash flow hedges	(509)	(232)
Net unrealized gain/ (loss) on other	0	0
Other comprehensive income/ (loss), net of tax	1,817	892
Total comprehensive income/ (loss), attributable to the Company, net	$ 20,600us-gaap_ComprehensiveIncomeNetOfTax	$ 17,933us-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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