|
CAPITAL STOCK (Details) (USD $)
In Millions, except Share data, unless otherwise specified |
1 Months Ended | 6 Months Ended | 12 Months Ended | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Mar. 13, 2012
|
Jul. 12, 2011
|
Jun. 13, 2011
|
Dec. 31, 2011
|
Jun. 30, 2011
|
Dec. 31, 2012
|
Dec. 31, 2011
|
Dec. 31, 2010
|
Dec. 03, 2012
|
Aug. 31, 2012
|
Jun. 01, 2012
|
Mar. 01, 2012
|
Dec. 01, 2011
|
Sep. 01, 2011
|
Aug. 15, 2011
|
Jun. 01, 2011
|
May 25, 2011
|
Mar. 01, 2011
|
|
| Class of Stock [Line Items] | ||||||||||||||||||
| Dividend payable, per share | $ 0.625 | $ 0.625 | $ 0.625 | $ 0.28 | $ 0.28 | $ 0.28 | $ 0.14 | $ 0.14 | ||||||||||
| Percentage increase in dividends payable | 123.00% | 100.00% | ||||||||||||||||
| Share repurchase plan, number of common shares authorized for repurchase | 4,000,000 | |||||||||||||||||
| Share buyback | $ 289.8 | $ 289.8 | ||||||||||||||||
| Shares repurchased, average price (in usd per share) | $ 72.44 | |||||||||||||||||
| Issuance of common shares, public offering (in shares) | 10,350,000 | |||||||||||||||||
| Common shares, issued (in shares) | 149,195,469 | 149,195,469 | 149,195,469 | |||||||||||||||
| Net proceeds from issuance of common shares | $ 854.0 | $ 0 | $ 853.7 | $ 0 | ||||||||||||||
| Closing price per share (in usd per share) | $ 85.63 | |||||||||||||||||
| Common shares, authorized (in shares) | 400,000,000 | 400,000,000 | 400,000,000 | 224,000,000 | ||||||||||||||
| Total shares authorized (in shares) | 231,000,000 | |||||||||||||||||
|
Maximum [Member]
|
||||||||||||||||||
| Class of Stock [Line Items] | ||||||||||||||||||
| Common shares, authorized (in shares) | 400,000,000 | |||||||||||||||||
| Total shares authorized (in shares) | 407,000,000 | |||||||||||||||||
|
Common Shares [Member]
|
||||||||||||||||||
| Class of Stock [Line Items] | ||||||||||||||||||
| Common shares, issued (in shares) | 9,000,000 | |||||||||||||||||
|
Over Allotment Option [Member]
|
||||||||||||||||||
| Class of Stock [Line Items] | ||||||||||||||||||
| Common shares, issued (in shares) | 1,350,000 | |||||||||||||||||
|
Preferred Class A [Member]
|
||||||||||||||||||
| Class of Stock [Line Items] | ||||||||||||||||||
| Preferred stock, shares authorized (in shares) | 3,000,000 | 3,000,000 | 3,000,000 | 3,000,000 | ||||||||||||||
|
Preferred Class B [Member]
|
||||||||||||||||||
| Class of Stock [Line Items] | ||||||||||||||||||
| Preferred stock, shares authorized (in shares) | 4,000,000 | 4,000,000 | 4,000,000 | 4,000,000 | ||||||||||||||