Note 16 - Disclosures About Fair Value - Fair Value of Mortgage Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Marketable securities, available-for-sale
Marketable securities, available-for-sale	$ 24,529
Fair Value, Inputs, Level 2 [Member]
Marketable securities, available-for-sale
Mortgage loans held for sale	158,804	$ 265,542
Fair Value, Inputs, Level 2 [Member] | US States and Political Subdivisions Debt Securities [Member]
Marketable securities, available-for-sale
Marketable securities, available-for-sale	9,387	9,387
Fair Value, Inputs, Level 3 [Member] | Metropolitan District Bond Securities [Member]
Marketable securities, available-for-sale
Marketable securities, available-for-sale	$ 15,142	$ 8,711