Fair Value Measurements - Schedule of Fair Value of Long-term Borrowings (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Long-term Borrowings:
Carrying amount of senior notes	$ 223,923	$ 201,653	$ 201,389
10.5% senior notes due 2018 [Member] | Significant Other Observable Inputs (Level 2) [Member]
Long-term Borrowings:
Carrying amount of senior notes		201,653	201,389
Estimated fair value of senior notes		229,152	214,894
6.625% senior notes due 2021 [Member] | Significant Other Observable Inputs (Level 2) [Member]
Long-term Borrowings:
Carrying amount of senior notes	223,923
Estimated fair value of senior notes	$ 229,500