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Basis of Presentation (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 | Mar. 31, 2017 | Mar. 31, 2018 | Mar. 31, 2017 | Oct. 01, 2017
New accounting pronouncements |  |  |  |  |
Increase in cash provided by operating activities |  |  | $ 196,994 | $ 150,278 |
Decrease in net cash used in financing activities |  |  | (157,579) | (148,350) |
Other disclosures |  |  |  |  |
Early termination revenue | $ 4,000 | $ 6,200 | 8,300 | 19,700 |
Abandonments | 8,200 | 18,600 | 15,500 | 19,400 |
Foreign currency (gain) loss | (200) | $ 600 | 1,400 | 2,000 |
ASU 2016-09 |  |  |  |  |
New accounting pronouncements |  |  |  |  |
Increase in cash provided by operating activities |  |  |  | 3,900 |
Decrease in net cash used in financing activities |  |  |  | $ 3,900 |
Cumulative effect adjustment | $ 317 |  | $ 317 |  | $ 300

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