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Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Mar. 31, 2018 | Mar. 31, 2017
Earnings Per Share [Abstract] |  |  |  |
Income from continuing operations | $ 178,992 | $ 162,012 | $ 493,124 | $ 276,050
Income allocated to participating securities | 161 | 193 | 459 | 348
Income from continuing operations available to common shareholders | $ 178,831 | $ 161,819 | $ 492,665 | $ 275,702
Income (Loss) from Continuing Operations, Per Basic and Diluted Share | $ 1.60 | $ 1.52 | $ 4.47 | $ 2.61
Income from discontinued operations, net of tax | $ 0 | $ 2,716 | $ 0 | $ 13,710
Undistributed Earnings From Discontinued Operations Allocated To Participating Securities | 0 | 2 | 0 | 15
Income from discontinued operations available to common shareholders | $ 0 | $ 2,714 | $ 0 | $ 13,695
Income (Loss) from Discontinued Operation, Net of Tax, Per Basic and Diluted Share | $ 0.00 | $ 0.03 | $ 0.00 | $ 0.13
Basic and diluted net income per share | $ 1.60 | $ 1.55 | $ 4.47 | $ 2.74
Weighted Average Number of Shares Outstanding, Basic and Diluted | 111,706 | 105,935 | 110,135 | 105,610

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- Definition The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. + References No definition available. + Details
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