Investments - Schedule of Available-For-Sale Investment Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Amortized Cost
Due in less than 1 year	$ 43,285	$ 45,391
Due in 1-5 years	10,810	13,204
Total	54,095	58,595
Fair Value
Due in less than 1 year	43,245	45,344
Due in 1-5 years	10,784	13,175
Total	$ 54,029	$ 58,519