Shareholders' Equity - Redomestication Narrative (Details) - USD ($)	Feb. 23, 2017	Dec. 31, 2016	Dec. 31, 2015	Aug. 31, 2015	Nov. 30, 2014
Subsequent Event [Line Items]
Distributable reserves available amount		$ 1,600,000,000	$ 2,100,000,000
Share Repurchase Program of 2014
Subsequent Event [Line Items]
Share repurchase authorization limit				$ 5,000,000,000	$ 5,000,000,000.0
Share Repurchase Program of 2014 | Subsequent Event
Subsequent Event [Line Items]
Share repurchase authorization limit	$ 5,000,000,000.0