Note 7 - Investments Investments In Any Person And Its Affiliates That Exceed 10% of Total Stockholders' Equity (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013 Investments in Any Person and Its Affiliates That Exceed 10 Percent of Total Stockholders Equity [Member]	Dec. 31, 2013 Debt Securities	Dec. 31, 2012 Debt Securities	Dec. 31, 2013 Northern Institutional Treasury Portfolio [Member] Investments in Any Person and Its Affiliates That Exceed 10 Percent of Total Stockholders Equity [Member]	Dec. 31, 2013 State of Illinois [Member] Investments in Any Person and Its Affiliates That Exceed 10 Percent of Total Stockholders Equity [Member]	Dec. 31, 2013 BlackRock Liquidity Funds T-Fund Money Market [Member] [Member] Investments in Any Person and Its Affiliates That Exceed 10 Percent of Total Stockholders Equity [Member]	Dec. 31, 2013 Vanguard Institutional Index Fund [Member] Investments in Any Person and Its Affiliates That Exceed 10 Percent of Total Stockholders Equity [Member]	Dec. 31, 2013 Federated Treasury Obligations Fund [Member] Investments in Any Person and Its Affiliates That Exceed 10 Percent of Total Stockholders Equity [Member]	Aug. 31, 2013 Mortgage Insurance Segment 2013 Freddie Mac Agreement [Member] Primary Mortgage Product [Member] First Lien Position [Member]
Investment Holdings [Line Items]
Restricted Investments Held as Collateral for Master Transaction Agreement, Net											$ 205,000,000
Trading securities—at fair value	3,117,429,000	4,094,622,000	103,348,000			0	103,348,000	0	0	0
Short-term investments—at fair value			599,989,000			399,559,000	0	100,980,000	0	99,450,000
Total	4,931,157,000	5,152,418,000	831,623,000			399,559,000	103,348,000	100,980,000	128,286,000	99,450,000
Available-for-sale Securities, Equity Securities	135,168,000	112,139,000	128,286,000						128,286,000	0
Assets Held by Insurance Regulators				17,000,000	18,000,000
Funds Held under Reinsurance Agreements, Asset				$ 317,100,000	$ 172,600,000