XML 111 R92.htm IDEA: XBRL DOCUMENT v3.8.0.1
Note 11 - Marketable Securities (Details Textual) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Payments to Acquire Marketable Securities $ 9,822 $ 2,466 $ 257
Proceeds from Sale and Maturity of Marketable Securities $ 3,146 $ 1,937 76,170
Available-for-sale Securities, Gross Realized Gains     39,900
Maximum [Member]      
Held-to-maturity Securities, Debt Maturities, Period 5 years    
Certain Marketable Securities [Member]      
Proceeds from Sale and Maturity of Marketable Securities     $ 76,200