Note 1 - Summary of Significant Accounting Policies (Details Textual)	12 Months Ended
	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares	Sep. 30, 2020 USD ($)	Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)
Incremental Costs of Obtaining a Contract, Deferred During Period	$ 3,700,000	$ 3,600,000	$ 2,600,000
Capitalized Contract Cost, Net, Noncurrent	4,555,000	4,204,000
Capitalized Computer Software, Additions	2,700,000	4,100,000
Asset Impairment Charges, Total	0	0	0
Impairment of Intangible Assets (Excluding Goodwill), Total	0	0	0
Goodwill, Impairment Loss	714,000	0	0
Goodwill, Ending Balance	57,255,000	57,935,000	57,831,000
Proceeds from Insurance Settlement, Investing Activities	260,000
Income Tax Credits and Adjustments	45,000	24,000	$ 0
Cash Equivalents, at Carrying Value, Total	5,000,000.0	3,700,000
Operating Lease, Right-of-Use Asset	1,308,000	1,628,000			$ 2,300,000
Accrued Liabilities and Prepaid Expenses, Net					43,000
Sales and Excise Tax Payable		775,000
Excess Loss Coverage Per Person	150,000
Self Insurance Reserve, Current	$ 418,000	$ 270,000
Common Class A [Member]
Stock Options Excluded from Computation of Earnings Per Share, Amount (in shares) | shares	65,127	16,221	93,346
WASHINGTON
Sales and Excise Tax Payable (Reversal of Liability)				$ (268,000)
Other Current Liabilities and Other Noncurrent Liabilities [Member]
Operating Lease, Liability, Total	$ 1,357,000	$ 1,663,000			$ 2,300,000
Cyber Attack [Member] | Recoveries Received Direct by the Company [Member]
Proceeds from Insurance Settlement, Operating Activities	3,300,000
Cyber Attack [Member] | Recoveries Paid Directly by Insurer to Outside Vendor [Member]
Proceeds from Insurance Settlement, Operating Activities	447,000
Cyber Attack [Member] | Reimbursement for Lost Revenue [Member]
Insurance Recoveries	533,000
Canadian Subsidiary [Member]
Goodwill, Impairment Loss	$ 714,000
Number of Customers	1
Goodwill, Ending Balance	$ 1,600,000
Selling, General and Administrative Expenses [Member]
Capitalized Contract Cost, Impairment Loss	63,000	$ 22,000	$ 51,000
Other Income [Member] | Property Damage Excluding Cyber Attack [Member]
Proceeds from Insurance Settlement, Investing Activities	$ 260,000
Minimum [Member]
Capitalized Contract Cost, Amortization Period (Year)	3 years
Minimum [Member] | Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Minimum [Member] | Computer Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Minimum [Member] | Software and Software Development Costs [Member]
Property, Plant and Equipment, Useful Life (Year)	1 year
Minimum [Member] | Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Maximum [Member]
Capitalized Contract Cost, Amortization Period (Year)	5 years
Maximum [Member] | Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life (Year)	10 years
Maximum [Member] | Computer Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Maximum [Member] | Software and Software Development Costs [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Maximum [Member] | Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life (Year)	40 years
Accounting Standards Update 2014-09 [Member] | Changes Related to Contract Costs [Member]
Capitalized Contract Cost, Gross						$ 3,400,000
Accounting Standards Update 2014-09 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Revenue Recognition [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance						2,700,000
Accounting Standards Update 2014-09 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Income Tax Related to Revenue Adjustment [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance						814,000
Accounting Standards Update 2014-09 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Changes Related to Contract Costs [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance						2,600,000
Accounting Standards Update 2014-09 [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | Changes Related to Contract Costs, Income Tax Effect [Member]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance						$ 776,000