Represents the amount of interest expense incurred during the period related to deferred compensation plans.

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- Definition

Aggregate number of common shares reserved for future issuance.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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- Definition

Amount of cost for defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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No definition available.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Note 15 - Benefit Plans (Details Textual) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	5.00%				4.25%
Defined Contribution Plan, Cost		$ 1.6	$ 1.3	$ 1.2
Interest Expense, Deferred Compensation Plan		$ 0.1
Common Stock Including Additional Paid in Capital [Member]
Stock Issued During Period, Shares, Employee Stock Purchase Plans		1,579	1,351	1,362
Stock Purchase Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance	250,000	250,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	242,500	242,500
Maximum [Member]
Interest Expense, Deferred Compensation Plan			$ 0.1	$ 0.1
Other Liabilities [Member]
Deferred Compensation Liability, Current and Noncurrent, Total	$ 3.0	$ 3.0	$ 3.2