2. Liquidity (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Restricted cash	$ 800,000	$ 150,000	$ 0
Letter of Credit 1
Restricted cash	150,000	150,000
Letter of Credit 2
Restricted cash	400,000	0
Letter of Credit 3
Restricted cash	$ 250,000	$ 0

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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-SubTopic 210
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-Subparagraph (SX 210.7-03(a)(2))
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Name:	us-gaap_RestrictedCashAndCashEquivalents
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant