Note 2 - Cash and Cash Equivalents (Details Textual) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Cash, Uninsured Amount	$ 5,349,977	$ 5,991,573
Cash, FDIC Insured Amount	$ 250,000

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

No definition available.

Name:	us-gaap_CashFDICInsuredAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant