Accounts Receivable, Short-Term and Long-Term Notes Receivable (Details) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
Accounts Receivable
Accounts receivable, reserve	$ 1,820,000
Current [Member]
Customer Notes Receivable
Gross notes receivable	766,675	$ 793,988
Notes receivable reserve	749,638	767,138
Net notes receivable	17,037	26,850
Accounts Receivable
Accounts receivable, gross	1,001,665	921,829
Accounts receivable, reserve	669,461	629,461
Accounts receivable, net	332,204	292,368
Long-Term [Member]
Customer Notes Receivable
Gross notes receivable	406,888	414,665
Notes receivable reserve	400,901	399,401
Net notes receivable	5,987	15,264
Accounts Receivable
Accounts receivable, gross	0	0
Accounts receivable, net	$ 0	$ 0