Nature of Activities and Significant Accounting Policies (Details)	12 Months Ended
	Dec. 31, 2016 property segment	Dec. 31, 2015
Nature of activities
Number of Reportable Segments | segment	1
Loans
Period of past due loans considered as impaired	90 days
Tax credit real estate
Number of multi family rental properties	2
Number of assisted living rental properties	3
Number of multi tenant rental properties for persons with disabilities	1
Number of multi family senior living rental properties	1
Ownership interest in each limited partnership (or greater)	99.00%
Duration of tax credit of each property	10 years
Deferred income taxes
Recognized income tax positions, maximum realized (in hundredths)	50.00%
Building and Improvements [Member] | Minimum [Member]
Property and equipment
Estimated useful lives	7 years	7 years
Building and Improvements [Member] | Maximum [Member]
Property and equipment
Estimated useful lives	40 years	40 years
Furniture and Equipment [Member] | Minimum [Member]
Property and equipment
Estimated useful lives	3 years	3 years
Furniture and Equipment [Member] | Maximum [Member]
Property and equipment
Estimated useful lives	10 years	10 years