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Shareholders' Equity (Details) - $ / shares | Oct. 29, 2015 | Jul. 23, 2015 | Apr. 22, 2015 | Jan. 29, 2015 | Sep. 30, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Dec. 31, 2013
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Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Declared quarterly cash dividend |  | $ 0.18 | $ 0.18 | $ 0.16 |  |  |  |
Special Dividends Payable, Amount Per Share |  | $ 0.16 | $ 0.16 | $ 0.14 |  |  |  |
Dividend Declared [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Declared quarterly cash dividend | $ 0.18 |  |  |  |  |  |  |
Special Dividends Payable, Amount Per Share | $ 0.18 |  |  |  |  |  |  |
Preferred Stock [Member] |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, New Issues |  |  |  |  | 8,782 | 8,782 | 8,782 | 8,782

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- Definition Special Dividends Payable, Amount Per Share + References No definition available. + Details
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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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- Definition Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 + Details
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- Details
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