Business combinations - Pro Forma Results (Details) - USD ($) $ / shares in Units, $ in Thousands |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
Mar. 31, 2021 |
Mar. 31, 2020 |
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| Business Combinations [Abstract] | ||||
| Revenue | $ 994,751 | $ 867,740 | $ 1,996,377 | $ 1,735,404 |
| Net income | $ 83,289 | $ 28,013 | $ 151,270 | $ 82,530 |
| Basic earnings per share (in dollars per share) | $ 1.34 | $ 0.44 | $ 2.44 | $ 1.28 |
| Diluted earnings per share (in dollars per share) | $ 1.34 | $ 0.44 | $ 2.43 | $ 1.28 |
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- Definition Per basic share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Per diluted share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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