XML 53 R42.htm IDEA: XBRL DOCUMENT v3.7.0.1
Marketable Securities (Details 2) - USD ($)
$ in Thousands
Jun. 30, 2017
Dec. 31, 2016
Cash equivalents and marketable securities, Continuous unrealized loss position    
Less than one year, Fair Value $ 42,665 $ 72,772
Unrealized gain (loss), Gross    
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (4) (21)
US Treasury and Government Short-term Debt Securities [Member]    
Cash equivalents and marketable securities, Continuous unrealized loss position    
Less than one year, Fair Value 8,997 18,395
Unrealized gain (loss), Gross    
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 0
Corporate Debt Securities [Member]    
Cash equivalents and marketable securities, Continuous unrealized loss position    
Less than one year, Fair Value 33,668 54,377
Unrealized gain (loss), Gross    
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss $ (4) $ (21)