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International Risk Factors (Details) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2016 USD ($) | Jun. 30, 2015 USD ($) | Jun. 30, 2016 USD ($) item | Jun. 30, 2015 USD ($) | Jun. 30, 2010 item
Number of rigs expropriated by Venezuelan government |  |  |  |  | 11
Foreign currency losses | $ | $ (1.1) | $ (0.3) | $ (9.4) | $ 1.5 |
Operating revenues | Geographic concentration risk | South America |  |  |  |  |
Concentration percentage |  |  | 80.70% |  |
Minimum |  |  |  |  |
Number of geographical areas of operation to minimize risks |  |  | 1 |  |
Contract Drilling: | Operating revenues | Geographic concentration risk | International locations |  |  |  |  |
Concentration percentage |  |  | 13.30% |  |

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