Subsequent Events (Details) (Subsequent Event [Member]) In Millions, unless otherwise specified			0 Months Ended
	May 09, 2014 USD ($)	May 09, 2014 EUR (€)	May 09, 2014 Opera Portfolio [Member] USD ($)	May 09, 2014 Opera Portfolio [Member] EUR (€)	May 09, 2014 Central Park Portfolio [Member] USD ($)	May 09, 2014 Central Park Portfolio [Member] EUR (€)	May 09, 2014 Office Building [Member] Opera Portfolio [Member] Property	May 09, 2014 Dublin, Ireland [Member] Retail [Member] Opera Portfolio [Member] Property	May 09, 2014 Dublin, Ireland [Member] Residential [Member] Central Park Portfolio [Member] residential_unit	May 09, 2014 Dublin, Ireland [Member] Commercial Real Estate [Member] Central Park Portfolio [Member] sqft	May 09, 2014 Dublin, Ireland [Member] Partially Completed Residential Development [Member] Central Park Portfolio [Member] residential_unit	May 09, 2014 Dublin, Ireland [Member] Commercial Real Estate in Partially Completed Residential Development [Member] Central Park Portfolio [Member] sqft	May 09, 2014 Cork, Ireland [Member] Retail [Member] Opera Portfolio [Member] Property
Subsequent Event [Line Items]
Number of properties in portfolio							7	6					1
Total sales price			$ 541.7	€ 391.4	$ 121.9	€ 88.1
Equity method investment, cash	130.7	94.4	269.7	194.9	42.5	30.7
Equity method investment, debt			272.0	196.5	79.4	57.4
Equity method investment, number of units in portfolio									272		166
Equity method investment, square feet in portfolio										31,000		14,800
Ownership percentage sold			25.00%	25.00%
Entitled promotion fee			$ 20.8	€ 15.0