Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Office Properties and Equipment, net (FY) (Details) - USD ($) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Office Properties and Equipment [Abstract]
Office properties and equipment, gross			$ 6,398	$ 5,630
Less accumulated depreciation			(3,615)	(3,388)
Office properties and equipment, net	$ 2,714		2,783	2,242
Depreciation expense	$ 170	$ 171	227	241
Land [Member]
Office Properties and Equipment [Abstract]
Office properties and equipment, gross			572	572
Office Buildings and Improvements [Member]
Office Properties and Equipment [Abstract]
Office properties and equipment, gross			3,268	3,264
Rights of Use Assets [Member]
Office Properties and Equipment [Abstract]
Office properties and equipment, gross			727	0
Furniture, Fixtures and Equipment [Member]
Office Properties and Equipment [Abstract]
Office properties and equipment, gross			$ 1,831	$ 1,794