Condensed Consolidated Statements of Cash Flows (Unaudited) (Parentheticals) - shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Conversion of Series H Preferred Stock Into Common Stock [Member]
Convertible preferred stock (in shares)	1,686
Conversion of stock, shares issued (in shares)	469,697
Conversion of Series I Preferred Stock Into Common Stock [Member]
Convertible preferred stock (in shares)	700
Conversion of stock, shares issued (in shares)	204,371
Stock Purchase Warrants First Issuance [Member]
Common stock issued (in shares)	145,866
Stock purchase warrants exercised (in shares)	188,688

The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration