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Consolidated Statements of Stockholders' Equity (unaudited) (Parenthetical) - $ / shares | 6 Months Ended
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Jun. 30, 2015 | Jun. 30, 2014
Consolidated Statements of Stockholders' Equity (unaudited) [Abstract] |  |
Cash dividends - per share (in dollars per share) | $ 0.43 | $ 0.42
Purchase of treasury shares (in shares) | 433,351 | 3,288
Net issuance of shares to employee benefit plans and other stock plans, including tax benefit (in shares) | 222,326 | 189,036

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- Definition Number of shares issued during the period to an employee benefit plans and other stock plans. + References No definition available. + Details
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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 Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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