Fresh Start Accounting - Adjustment in Fair Value and Reorganization (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 19, 2012
Adjustment in fair value and reorganization
Predecessor retained earnings	$ 101,677
Adjustment for carve-out allocations	23,109
Predecessor adjusted retained earnings	(124,786)
Predecessor additional paid-in capital	69,879
Predecessor common stock eliminated in consolidation	(1)
Predecessor [Member]
Adjustment in fair value and reorganization
Predecessor retained earnings	101,677
Adjustment for carve-out allocations	23,109
Predecessor adjusted retained earnings	124,786
Predecessor additional paid-in capital	69,879
Predecessor common stock eliminated in consolidation	(1)
Predecessor equity value	194,664
Fair Value Adjustments [Member]
Adjustment in fair value and reorganization
Fair market value of WMMRC	131,600
Loss contract fair market reserve allowance	$ 63,064

Amount of fresh-start adjustment to retained earnings or deficit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 55

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=34712771&loc=d3e56426-112766

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 852

-SubTopic 10

-Section 45

-Paragraph 21

-URI http://asc.fasb.org/extlink&oid=6916575&loc=d3e55811-112764

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