Note 17 - Subsequent Events	9 Months Ended
Sep. 30, 2020
Notes to Financial Statements
Subsequent Events [Text Block]	17. Subsequent Events: In September 2020, the Company entered into an additional ASR agreement with Citibank, N.A. to repurchase shares of its common stock for an aggregate purchase price of $50.0 million. Upon payment of the aggregate purchase price on October 1, 2020, the Company received an initial delivery of 215,855 shares of its common stock at a price of $185.31 per share, representing approximately $40.0 million of the aggregate purchase price. Upon the final settlement of the ASR agreement in December 2020, the Company may be entitled to receive additional shares of its common stock or, under certain limited circumstances, be required to deliver shares to the counter-party. See Note 11. Stockholders' Equity for further discussion.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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