v3.3.1.900
Investments - Cost and Fair Value of Debt Investments Based on Maturities (Detail) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Available-for-sale Securities, Debt Maturities [Abstract]    
Due in one year or less, Amortized Costs $ 152,444 $ 70,180
Due within two years, Amortized Costs 130,110 62,184
Total, Amortized Costs 282,554 132,364
Due in one year or less, Fair Value 152,212 70,169
Due within two years, Fair Value 129,466 61,948
Total, Fair Value $ 281,678 $ 132,117