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CONDENSED CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (Parenthetical) - $ / shares | 3 Months Ended | 9 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Common Stock, Dividends, Per Share, Declared | $ 0.05 | $ 0.05 | $ 0.10 | $ 0.10
1.50% Senior Convertible Notes Due 2021 [Domain] | Senior Notes [Member] |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 1.50% |  | 1.50% |

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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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