Note 12 - Other Liabilities Components of Other Liabilities (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Other Liabilities [Abstract]
Deferred ceding commission		$ 92,987	$ 89,907
FHLB advances		71,430	0
Accrued compensation		48,712	67,687
Payable for securities	[1]	43,076	1,000
Amount payable on the return of cash collateral under securities lending agreements		31,799	19,357
Current federal income taxes		11,278	96,740
Other		80,080	79,154
Total other liabilities		$ 379,362	$ 353,845

[1] Represents the payable for purchases of securities that have not yet settled as of the balance sheet date.