SHAREHOLDERS' INTEREST - Additional Information (Details) $ / shares in Units, $ in Millions			1 Months Ended	12 Months Ended
	Jul. 01, 2016 shares	Jun. 24, 2013 USD ($) $ / shares Rate shares	Jun. 28, 2016 $ / shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) shares	Jun. 30, 2017	Nov. 08, 2015 USD ($)	Aug. 27, 2015 USD ($)	Aug. 13, 2014 USD ($)
Class of Stock [Line Items]
Preference shares conversion ratio	1.6929							1.5283
Shares issued upon conversion of stock	23,200,000			0	23,345,000	0
Volume weighted average price per share | $ / shares			$ 29.54
Stock repurchase program, shares repurchased				0	67,817,000	16,190,000
Common shares, outstanding				755,222,727	748,528,131	510,483,000	524,474,000
Stock repurchase program 2014 (2014 Program)
Class of Stock [Line Items]
Stock repurchase program, authorized repurchase amount | $											$ 700
Stock repurchase program, shares repurchased						15,471,962	6,062,993
Stock repurchase program, value repurchased | $						$ 497	$ 203
Stock repurchase program August 2015 (2015 Program)
Class of Stock [Line Items]
Stock repurchase program, authorized repurchase amount | $										$ 500
Stock repurchase program, shares repurchased						717,464
Stock repurchase program, value repurchased | $						$ 22
Stock repurchase program, remaining authorized repurchase amount | $					$ 478
Stock repurchase program November 2015 (2016 Program)
Class of Stock [Line Items]
Stock repurchase program, authorized repurchase amount | $									$ 2,500
Stock repurchase program, shares repurchased					67,816,810
Stock repurchase program, value repurchased | $					$ 2,000
Stock repurchase program, remaining authorized repurchase amount | $				$ 500
Unsettled share repurchases
Class of Stock [Line Items]
Stock repurchase program, shares repurchased				0	0
Preferred shares
Class of Stock [Line Items]
Preferred shares, outstanding				0	0
Preferred shares, authorized				7,000,000
Preferred shares, par value | $ / shares				$ 1
6.375 percent Mandatory Convertible Preference Shares, Series A
Class of Stock [Line Items]
Preferred shares, outstanding	13,700,000					13,800,000
Preferred shares, par value | $ / shares		$ 1.00				$ 1.00
New issuance		13,800,000
Preference shares, liquidation | $ / shares		$ 50.00				$ 50.00
Net proceeds from issuance of preference shares | $		$ 669
Preferred shares, dividend rate | Rate		6.375%