Fair Value Measurements - Difference Between Fair Values and Aggregate Contractual Amounts (Detail) (USD $) In Thousands, unless otherwise specified	Jul. 31, 2014	Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value at July 31, 2014	$ 226	$ 226
Amount Due Upon Maturity	1,130
Difference	904
Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value at July 31, 2014	226	226
Amount Due Upon Maturity	1,130
Difference	$ 904