Note 12 - Recent Accounting Pronouncements (continued) (Details Textual) - USD ($)	Jan. 01, 2019	Mar. 31, 2019
Operating Lease, Liability, Total		$ 1,820,000
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset	$ 1,600,000
Operating Lease, Liability, Total	1,800,000
Cumulative Effect on Retained Earnings, Net of Tax, Total	170,000
Cumulative Effect on Retained Earnings, Tax	45,000
Accounting Standards Update 2017-08 [Member]
Cumulative Effect on Retained Earnings, Net of Tax, Total	10,000
Cumulative Effect on Retained Earnings, Tax	$ 3,000

Amount of the cumulative effect on retained earnings net of related income tax effect.

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Amount of the related income tax effect of a cumulative effect on retained earnings.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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