Goodwill - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2015 USD ($)
Goodwill [Line Items]
Goodwill impairment charge	$ 20
Diamond Offshore Drilling, Inc. [Member]
Goodwill [Line Items]
Goodwill impairment charge	$ 20

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.

No definition available.

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