Equity - Noncontrolling Interests (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Noncontrolling Interest [Line Items]
Noncontrolling interests	$ 1,492.2	$ 1,731.3
KWE [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interests	$ 1,300.0
Ownership percentage by parent	21.60%	18.20%
Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Noncontrolling interests	$ 1,500.0	$ 1,700.0