Note 10 - Stock Repurchase Program (Details Textual) - Repurchase Program 2009 [Member] - USD ($) shares in Thousands	9 Months Ended
Dec. 31, 2021	Aug. 27, 2015	Jan. 21, 2009
Stock Repurchase Program, Authorized Amount			$ 2,500,000
Stock Repurchase Program Authorized Additional Amount		$ 5,000,000
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 3,762,040
Treasury Stock, Shares, Acquired (in shares)	0

Number of shares that have been repurchased during the period and are being held in treasury.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration