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Earnings Per Share Earnings Per Share - Additional Information (Details) (USD $) In Thousands, except Share data, unless otherwise specified | 0 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 09, 2013 | Sep. 30, 2014 | Dec. 31, 2013 | Dec. 09, 2013
Class of Stock [Line Items] |  |  |  |
Common stock, par value (in dollars per share) |  | $ 0.01 | $ 0.01 |
Shares issued, price per share |  |  |  | $ 44.94
Proceeds from issuance of common stock, net of discounts and expenses | $ 314,400 |  |  |
Common Stock [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Issuance of common stock, shares | 7,000,000 |  |  |
Common stock, par value (in dollars per share) |  |  |  | $ 0.01
Additional Paid-in-Capital [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Proceeds from issuance of common stock, net of discounts and expenses | 314,300 |  |  |
Common Stock [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Proceeds from issuance of common stock, net of discounts and expenses | $ 70 |  |  |

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