Note 6 - Fair Value Measurements - Amortized Cost and Estimated Fair Value of Available-for-sale Marketable Securities (Details) - Financial Services Segment [Member] - Cash and Cash Equivalents [Member] $ in Thousands	Dec. 31, 2018 USD ($)
Amortized Cost	$ 34,866
OTTI	0
Net Amortized Cost	34,866
Fair Value	$ 34,866