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Equity (Details) (USD $) In Millions, except Share data, unless otherwise specified | 9 Months Ended |
--- | --- | ---
Sep. 30, 2013 | Mar. 31, 2013
Equity [Abstract] |  |
Common stock issued under stock compensation plan (in shares) | 1,654,477 |
Increase in cash dividend rate (in dollars per share) |  | $ 0.01
Dividends payable (in dollars per share) | $ 0.14 | $ 0.14
Dividends payable | $ 20.3 |

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