Represents the minimum consolidated leverage ratio of credit facility.

No definition available.

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- Definition

Represents the average cost per share under the stock repurchase program.

+ References

No definition available.

+ Details

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 505
-SubTopic 10
-Section 50
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- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

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-SubTopic 10
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Note 10 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Apr. 30, 2019 shares	Apr. 30, 2018 shares	Dec. 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	1,043,607	1,034,964	1,143,205			1,428,878
A 2016 Employee Plan [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)				300,000	1,700,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	1,451,672
A 2016 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	250,980
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	163,973
A 2011 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	51,842
A 2006 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	29,529
A 2001 Director Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	19,125
Share-based Payment Arrangement, Option [Member]
Stock Repurchased During Period, Shares (in shares)		48,409
Stock Repurchased During Period, Value \| $		$ 1.0
Stock Repurchase Program, Average Cost Per Share (in dollars per share) \| $ / shares		$ 20.52
Amended Credit Facility [Member]
Credit Facility Minimum Consolidated Leverage Ratio	2.50	2.50
Stock Repurchase Program, Authorized Amount \| $	$ 40.0
Share Repurchase Program 2019 [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)		2,000,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased (in shares)	2,000,000
Share Repurchase Program 2018 [Member]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares)			2,000,000
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased (in shares)	125,975
In Connection With Equity Compensation Programs [Member]
Stock Repurchase Program, Authorized Amount \| $	$ 10.0
Stock Repurchased During Period, Shares (in shares)	122,292	151,234	228,068
Stock Repurchased During Period, Value \| $	$ 2.5	$ 3.1	$ 5.5
Stock Repurchase Program, Average Cost Per Share (in dollars per share) \| $ / shares	$ 20.57	$ 20.26	$ 24.08
The Open Market Repurchase Program [Member]
Stock Repurchased During Period, Shares (in shares)	381,677	1,492,348	949,464
Stock Repurchased During Period, Value \| $	$ 6.6	$ 26.3	$ 20.3
Stock Repurchase Program, Average Cost Per Share (in dollars per share) \| $ / shares	$ 17.16	$ 17.64	$ 21.36