The past due term for the financing receivable.

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Represents the number of portfolio segments.

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The period after completion cessation of cost capitalization of real estate under development.

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Amount of allowance for credit loss on accounts receivable.

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Amount of increase (decrease) of allowance reserve for credit loss.

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Amount of expense for amortization of capitalized computer software costs.

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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of assets classified as other.

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Amount of revenue and income classified as other.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of shares authorized for issuance under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Real Estate Under Development Period After Completion Cessation of Cost Capitalization (Year)	1 year
Number of Portfolio Segments	1
Financing Receivable Past Due Term (Day)	90 days
Capitalized Computer Software, Net, Ending Balance	$ 19,100	$ 14,500
Capitalized Computer Software, Amortization	3,200	1,700	$ 5,300
Other Assets, Total	$ 97,225	194,682
Revision of Prior Period, Reclassification, Adjustment [Member]
Other Assets, Total		9,400
Other Income		$ 800	$ (3,500)
Restricted Stock [Member] \| Share-based Compensation Award, Vesting on Fourth or Fifth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	100.00%
Restricted Stock [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	4 years
Restricted Stock [Member] \| Share-based Payment Arrangement, Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	5 years
Restricted Stock [Member] \| Share-based Compensation Award, Vesting After the Fifth Anniversary [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	10 years
The 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) \| shares	10,000,000
COVID 19 [Member]
Allowance for Loan and Lease Losses, Period Increase (Decrease), Total	$ 81,000
COVID 19 [Member] \| Straight-Line Rent Receivables [Member]
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 15,200
Minimum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	1 year
Minimum [Member] \| Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	3 years
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years
Maximum [Member] \| Computer Software, Intangible Asset [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	10 years
Building and Building Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Building and Building Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	50 years