Reconciliation of Enterprise Value to Estimated Fair Value of Successor's Common Stock (Detail) $ in Thousands	Jul. 31, 2017 USD ($)
Reorganizations [Abstract]
Enterprise Value	$ 1,050,000
Add: Cash and cash equivalents	560,866
Less: Amounts due to General Unsecured Creditors	(102,193)
Less: Fair value of debt	(451,589)
Less: Fair value of New Creditor, Series A and B warrants	(299,045)
Less: Fair value of noncontrolling interests	(1,675)
Fair Value of Successor common stock	$ 756,364

Postconfirmation Fair Value Of New Creditor And warrants.

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Postconfirmation Fair Value Of Noncontrolling Interests.

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Amount of accounts payable at the balance sheet date after fresh-start adjustments.

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Amount of cash and cash equivalents at the balance sheet date after fresh-start adjustments.

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Amount of common stock at the balance sheet date after fresh-start adjustments.

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Total long-term debt at the balance sheet date after fresh-start adjustments.

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Amount attributed to the reconstituted entity, as well as the expected net realizable value of those assets that will be disposed before reconstitution occurs.

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