SHAREHOLDERS' INTEREST - Reconciliation of Our Common Share Activity (Details) - shares	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Outstanding at beginning of year		524,474,315	583,548,000	542,393,000
New issuance (Note 4)		0	0	33,350,000
Shares tendered (Note 3)	(59,000,000)	0	(58,813,151)	0
Issued for restricted stock units		365,000	451,000	462,000
Repurchased		(16,190,000)	(6,063,000)	0
Outstanding at end of year		510,483,285	524,474,315	583,548,000
Stock options exercised
Class of Stock [Line Items]
Shares issued		1,592,000	5,134,000	7,209,000
Issued for performance shares
Class of Stock [Line Items]
Shares issued		242,000	217,000	134,000