Term Deposits with Various Banks Outstanding (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Term deposits outstanding	$ 517,210	$ 479,700
Cash & Cash Equivalents
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Term deposits outstanding	108,040	13,000
Short Term Investments
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Term deposits outstanding	409,090	466,600
Non Current Assets
Schedule of Fair Value of Separate Accounts by Major Category of Investment [Line Items]
Term deposits outstanding	$ 80	$ 100