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Stock Repurchase (Details) (USD $) | 9 Months Ended | 0 Months Ended |
--- | --- | --- | ---
Sep. 30, 2014 | Sep. 25, 2014 Share Repurchase Agreement with Capital Southwest Corporation and Capital Southwest Venture Corporation | Sep. 24, 2014 Share Repurchase Agreement with Capital Southwest Corporation and Capital Southwest Venture Corporation | Sep. 24, 2014 Share Repurchase Agreement with Capital Southwest Corporation and Capital Southwest Venture Corporation
Equity, Class of Treasury Stock [Line Items] |  |  |  |
Number of shares repurchased owned by Capital Southwest |  |  |  | 849,690
Purchase price per share |  |  | $ 40.255 |
Closing price of common stock |  |  |  | $ 41.50
Common Stock Issued and Outstanding [Roll Forward] |  |  |  |
Balance (shares) | 12,070,509 |  |  |
Exercise of stock options (shares) | 23,231 |  |  |
Retirement of shares (shares) | (849,690) | (849,690) |  |
Balance (shares) | 11,244,050 |  |  |

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- Definition Number of share options (or share units) exercised during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: 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 3: 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 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28,29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 6: 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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