Note I - Equity-based Compensation - Weighted-average Fair Value Assumptions (Details)	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Volatility	45.08%	34.96%
Risk-free interest rate	2.93%	2.14%
Dividend yield	0.00%	0.00%
Pre-vest cancellation rate	3.65%	4.31%
Post-vest cancellation rate	3.21%	3.37%
Suboptimal exercise factor	1.205%	1.117%

The post-vest cancellation rate assumption that is used in after cancelling an option of its own shares.

No definition available.

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- Definition

The pre-vest cancellation rate assumption that is used in before cancelling an option of its own shares.

+ References

No definition available.

+ Details

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- Definition

The suboptimal exercise factor of a fair value assumption in a share-based compensation arrangement.

+ References

No definition available.

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ 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 (f)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ 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 (f)(2)(iv)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

+ 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 (f)(2)(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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