Income Taxes and State LLC Fees (Narrative) (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Line Items]
Operating loss carryforward expiration	Dec. 31, 2030
California Franchise Tax Board [Member]
Income Tax Disclosure [Line Items]
Gross receipt fee based on turnover	$ 12,000
California Franchise Tax Board [Member] | Minimum [Member]
Income Tax Disclosure [Line Items]
State minimum franchise tax	800
MP Securities [Member] | California Franchise Tax Board [Member]
Income Tax Disclosure [Line Items]
Gross receipt fee based on turnover	6,000
MP Securities [Member] | California Franchise Tax Board [Member] | Minimum [Member]
Income Tax Disclosure [Line Items]
State minimum franchise tax	$ 800
MP Realty [Member]
Income Tax Disclosure [Line Items]
Operating loss carryforwards		$ 407,000	$ 402,000
Valuation allowance, percentage	100.00%	100.00%
MP Realty [Member] | California Franchise Tax Board [Member]
Income Tax Disclosure [Line Items]
Gross receipt fee based on turnover		$ 800	$ 800