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Note 7 - Goodwill and Other Acquired Intangible Assets, Net Impairment Analysis (Details) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) customer	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Finite-Lived Intangible Assets [Line Items]
Impairment of goodwill	$ 0	$ 0	$ 184,374	$ 0	$ 0	$ 184,374	$ 0
Finite-Lived Intangible Assets, Remaining Amortization Period					15 years
Mortgage and Real Estate Services Segment
Finite-Lived Intangible Assets [Line Items]
Impairment of goodwill			184,400		$ 0	$ 184,374
Impairment of Intangible Assets, Finite-lived			0		$ 0
Number of Customers with Renewed Contract Terms \| customer					1
Client relationships \| Mortgage and Real Estate Services Segment
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			14,900
Technology \| Mortgage and Real Estate Services Segment
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			900
Other Intangible Assets \| Mortgage and Real Estate Services Segment
Finite-Lived Intangible Assets [Line Items]
Impairment of Intangible Assets, Finite-lived			$ 15,800