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Amount of gain recognized in the period that had been disclosed in prior periods as a contingent gain.

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Amount awarded to other party in judgment or settlement of litigation.

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The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Minimum amount of purchase arrangement in which the entity has agreed to expend funds to procure goods or services from a supplier.

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Commitments and Contingencies (Details) - USD ($) $ in Millions	Sep. 30, 2016	Apr. 28, 2015	Jun. 30, 2017
Purchase obligations
Purchase orders outstanding for drilling equipment			$ 59.7
Gain contingencies recognized in consolidated financial statements			0.0
CONTINGENCIES
Gain contingencies recognized in consolidated financial statements			$ 0.0
Judicial ruling \| Keel accident case
CONTINGENCIES
Litigation settlement	$ 72.0
Judicial ruling \| Minimum \| Keel accident case
CONTINGENCIES
Damages value		$ 100.0