XML 55 R44.htm IDEA: XBRL DOCUMENT v3.10.0.1
Marketable Securities - Schedule of Amortized Cost and Estimated Fair Value of Marketable Securities Classified by Maturity Date (Details) - USD ($)
$ in Thousands
Sep. 30, 2018
Dec. 31, 2017
Available For Sale Securities Debt Maturities Fair Value [Abstract]    
Amortized Cost, Due within one year $ 63,901 $ 104,742
Amortized Cost, Due after one through five years 6,191 5,008
Amortized Cost, Due after five through ten years 0 0
Amortized Cost, Due after ten years 0 0
Amortized Cost, Total marketable securities 70,092 109,750
Fair Value, Due within one year 63,831 104,605
Fair Value, Due after one through five years 6,174 4,984
Fair Value, Due after five through ten years 0 0
Fair Value, Due after ten years 0 0
Fair Value, Total marketable securities $ 70,005 $ 109,589