Note 5 - Investments Securities Lending Agreements (Details) - USD ($)		Mar. 31, 2019	Dec. 31, 2018
Securities Financing Transaction [Line Items]
Loaned securities		$ 22,606,000	$ 27,860,000
Cash Collateral for Borrowed Securities		6,233,000	11,699,000
Securities Held as Collateral, at Fair Value		0
Securities Financing Transaction, Fair Value
Securities Financing Transaction [Line Items]
Loaned securities	[1]	22,606,000	27,860,000
Cash Collateral for Borrowed Securities	[2]	17,372,000	16,815,000
Reinvested Cash Collateral, Fair Value	[3]	6,233,000	11,699,000
Securities Financing Transaction, Fair Value | US government and agency securities
Securities Financing Transaction [Line Items]
Loaned securities	[1]	0	9,987,000
Securities Financing Transaction, Fair Value | Corporate bonds and notes
Securities Financing Transaction [Line Items]
Loaned securities	[1]	6,526,000	7,818,000
Securities Financing Transaction, Fair Value | Equity securities
Securities Financing Transaction [Line Items]
Loaned securities	[1]	16,080,000	10,055,000
Securities Financing Transaction, Cost
Securities Financing Transaction [Line Items]
Loaned securities		$ 22,537,000	$ 28,992,000

[1] Our securities loaned under securities lending agreements are reported at fair value within other assets in our condensed consolidated balance sheets. All of our securities lending agreements are classified as overnight and revolving. None of the amounts are subject to offsetting.

[2] Securities collateral on deposit with us from Borrowers may not be transferred or re-pledged unless the Borrower is in default, and is therefore not reflected in our condensed consolidated financial statements.

[3] All cash collateral received has been reinvested in accordance with the securities lending agreements and is included in short-term investments in our condensed consolidated balance sheets. Amounts payable on the return of cash collateral under securities lending agreements are included within other liabilities in our condensed consolidated balance sheets.