Consolidated Statements of Cash Flows (unaudited) (Parentheticals) - USD ($)	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Reconciliation to consolidated balance sheets:
Cash	$ 30,338,228	$ 32,827,390	$ 30,663,307
Restricted Cash	2,364,290	883,902	762,602
Subtotal- cash and restricted cash	$ 32,702,518	$ 33,711,292	$ 31,425,909	$ 23,944,874

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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant