Note 2 - Significant Accounting Policies Accounting Policy (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($) incident group payment days	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) incident group years payment days	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Significant Accounting Policies Line Items [Line Items]
Unbilled Contracts Receivable	$ 22,300								$ 22,300
Services revenue	39,703	$ 39,571	$ 37,802	$ 38,027	$ 49,905	$ 45,877	$ 40,263	$ 32,849	155,103	$ 168,894	$ 157,216
Cost of services	23,349	27,240	25,635	28,375	33,812	29,447	27,365	23,550	104,599	114,174	93,715
Other income									2,886	3,572	2,899
Other operating expenses	$ 65,999	$ 64,195	$ 68,750	$ 68,377	62,416	$ 62,119	$ 63,173	$ 57,188	$ 267,321	244,896	242,405
Losses and LAE Mortgage Insurance [Abstract]
Number of Natural Disasters | incident	2								2
Period That the Policyholder Has to Challenge a Notice of Rescission | days	30								30
Cash and Restricted Cash [Abstract]
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 96,200				61,800				$ 96,200	61,800
Cash and Cash Equivalents, at Carrying Value	80,569				52,149				80,569	52,149
Restricted cash	$ 15,675				$ 9,665				$ 15,675	9,665
Investments [Abstract]
Number of Investment Categories | group	3								3
Maximum Maturity Duration for Short Term Investment Grouping									3 months
Minimum [Member]
Losses and LAE Mortgage Insurance [Abstract]
Number Of Payments Missed For Insured Loans | payment	2								2
Maximum [Member]
Reserve for Premium Deficiency [Abstract]
Number Of Years That The Measurement Period Of The TCJA Is Not To Exceed | years									1
Computer Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Useful Life, Maximum									3 years
Computer Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Useful Life, Maximum									5 years
Furniture, Fixtures and Office Equipment [Member]
Property, Plant and Equipment, Net [Abstract]
Property, Plant and Equipment, Useful Life, Maximum									7 years
Mortgage Insurance Segment
Significant Accounting Policies Line Items [Line Items]
Services revenue									$ 0
Cost of services									0	0	0
Other income									2,886	3,572	2,899
Other operating expenses									$ 150,975	$ 140,624	$ 148,619
Losses and LAE Mortgage Insurance [Abstract]
Period of Time Insureds Have After Foreclosure To Provide Documents To Perfect Claim									1 year
Reserve for Premium Deficiency [Abstract]
Number of Mortgage Insurance Product Categories | group									2