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Equity (Narrative) (Details) - $ / shares |  | 3 Months Ended
--- | --- | ---
Apr. 06, 2016 | Mar. 31, 2016 | Mar. 31, 2015
Equity [Abstract] |  |  |
Stock Options Excluded From Diluted Common Shares Outstanding Calculation |  | 6,100,000 | 3,500,000
Common stock dividend (in dollars per share) |  | $ 0.85 | $ 0.83
Parent Company [Member] |  |  |
Equity [Abstract] |  |  |
Shares, Issued |  | 332,576 |
Subsequent Event [Member] |  |  |
Equity [Abstract] |  |  |
Common stock dividend (in dollars per share) | $ 0.85 |  |

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- Definition Aggregate dividends declared during the period for each share of common stock outstanding. + References Reference 1: 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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