Investments - Components of Company's Investments (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Total	$ 13,989	$ 13,848
U.S. Non-Qualified Deferred Compensation Plan [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Total	13,709	13,232
Warrants and Equity Securities [Member]
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Total	$ 280	$ 616