Fresh Start Financial Statement Reporting - Fresh Start Reorganized Condensed Consolidated Balance Sheet (Parenthetical) (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Apr. 30, 2013
Fresh-Start Adjustment [Line Items]
Common stock, shares issued	45,005,932	45,003,461	45,000,000
Number of warrants issued			5,047,138
Pre-tax gain on extinguishment of obligations			$ 1,521,435
Reorganization Item Adjustments [Member]
Fresh-Start Adjustment [Line Items]
Cash			(101,900)
Successor [Member]
Fresh-Start Adjustment [Line Items]
Cash			$ 152,951
Common stock, shares issued			45,000,000