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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Income Taxes, Effective Income Tax Rate Reconciliation (FY) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Provision of Income Taxes [Abstract]
Federal statutory rate			21.00%		21.00%
Federal statutory rate times financial statement net (loss) income					$ (115)	$ 183
Effect of [Abstract]
State taxes, net of federal benefit					(45)	77
Change in federal rate					0	0
Earnings from bank owned life insurance					(11)	(16)
Low income housing credits					(198)	(212)
Change in valuation allowance					0	0
Other, net					24	24
Total	$ 95	$ (176)	$ (300)	$ (262)	$ (345)	$ 56