Fair Value of Financial Instruments - Included in Notes Payable are Senior Notes and Subordinated Debentures (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Interest rate (percent)	5.28%	5.28%
Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Interest rate (percent)	3.96%	0.00%
Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Interest rate (percent)	1.73%	1.73%
Debt instrument, issued	$ 21,500,000
Federal Home Loan Bank of Cincinnati [Member]
Debt Instrument [Line Items]
Interest rate (percent)	0.00%	5.03%
Debt instrument, issued	$ 85,000,000.0
Affiliate Subordinated Debentures due 2033
Debt Instrument [Line Items]
Interest rate (percent)	6.94%	5.68%
Debt instrument, issued	$ 15,500,000
Carrying value
Debt Instrument [Line Items]
Total notes payable	122,000,000.0	$ 122,100,000
Carrying value | Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Total notes payable	85,300,000	0
Carrying value | Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Total notes payable	21,500,000	21,500,000
Carrying value | Federal Home Loan Bank of Cincinnati [Member]
Debt Instrument [Line Items]
Total notes payable	0	85,400,000
Carrying value | Affiliate Subordinated Debentures due 2033
Debt Instrument [Line Items]
Total notes payable	15,200,000	15,200,000
Fair value
Debt Instrument [Line Items]
Total notes payable	125,100,000	121,800,000
Fair value | Notes Payable to Banks [Member]
Debt Instrument [Line Items]
Total notes payable	89,000,000.0	0
Fair value | Federal Home Loan Bank Advances
Debt Instrument [Line Items]
Total notes payable	20,900,000	20,900,000
Fair value | Federal Home Loan Bank of Cincinnati [Member]
Debt Instrument [Line Items]
Total notes payable	0	85,700,000
Fair value | Affiliate Subordinated Debentures due 2033
Debt Instrument [Line Items]
Total notes payable	$ 15,200,000	$ 15,200,000