Note 11 - Losses and LAE Mortgage Insurance Loss Reserves Rollforward (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
		Sep. 30, 2017	Dec. 31, 2019		Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Loss reserve [Roll Forward]
Balance at January 1			$ 401,361		$ 507,588
Deduct paid claims and LAE related to [Abstract]
Balance at December 31					401,361		$ 507,588
Mortgage Insurance Segment
Loss reserve [Roll Forward]
Balance at January 1			397,891	[1]	507,588		760,269		$ 976,399
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	[2]		11,009		8,350		6,851		8,286
Balance at beginning of period, net of reinsurance recoverables			386,882		499,238		753,418		968,113
Add losses and LAE incurred in respect of default notices reported and unreported in [Abstract]
Current year	[3]				135,291		185,486		206,383
Prior years					(31,699)		(49,286)		(3,516)
Total incurred losses and LAE					103,592		136,200		202,867
Deduct paid claims and LAE related to [Abstract]
Paid Losses and LAE Current year	[3]				5,856		25,011		11,410
Paid losses and LAE Prior years					210,092		365,369		406,152
Total paid losses and LAE					215,948		390,380	[4]	417,562
Balance at end of period, net of reinsurance recoverables					386,882		499,238		753,418
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	[2]		$ 11,009		8,350		6,851		8,286
Balance at December 31					$ 397,891	[1]	$ 507,588		$ 760,269
2013 Freddie Mac Agreement | Mortgage Insurance Segment
Deduct paid claims and LAE related to [Abstract]
Paid losses and LAE Prior years		$ 54,800

[1] Excludes Services reserve for losses and LAE of $3.5 million.

[2] Related to ceded losses recoverable, if any, on reinsurance transactions, the QSR Program and the Single Premium QSR Program. See Note 8 for additional information.

[3] Related to underlying defaulted loans with a most recent default notice dated in the year indicated. For example, if a loan had defaulted in a prior year, but then subsequently cured and later re-defaulted in the current year, that default would be considered a current year default. For 2017, includes payments made on pool commutations, in some cases for loans not previously in default.

[4] Includes the payment of $54.8 million made in connection with the scheduled final settlement of the Freddie Mac Agreement in the third quarter of 2017.