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SUBSEQUENT EVENTS Subsequent Events (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 9 Months Ended |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2015 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Nov. 02, 2015 | Aug. 03, 2015 | May. 01, 2015 | Feb. 02, 2015 | Nov. 03, 2014 | Aug. 01, 2014 | May. 01, 2014
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Dividends, Preferred Stock |  | $ 25.6 | $ 12.8 | $ 38.4 | $ 38.4 |  |  |  |  |  |  |
Preferred Class A [Member] |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share |  |  |  |  |  |  | $ 17.50 | $ 17.50 | $ 17.50 | $ 17.50 | $ 17.50 | $ 17.50
Dividends, Preferred Stock |  | $ 25.6 | $ 12.8 | $ 38.4 | $ 38.4 |  |  |  |  |  |  |
Preferred Class A [Member] | Dividend Declared [Member] |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share |  |  |  |  |  | $ 17.50 |  |  |  |  |  |
Dividends, Preferred Stock | $ 12.8 |  |  |  |  |  |  |  |  |  |  |
Depositary Share [Member] |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share |  |  |  |  |  |  | $ 0.44 | $ 0.440 | $ 0.44 | $ 0.440 | $ 0.440 | $ 0.440
Depositary Share [Member] | Dividend Declared [Member] |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable, per share |  |  |  |  |  | $ 0.44 |  |  |  |  |  |

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- Definition The per share amount of a dividend declared, but not paid, as of the financial reporting date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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