Schedule II - Condensed Financial Information of Registrant - Balance Sheets Stock Information (Details) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, par value (in dollars per share)	$ 0	$ 0
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	8,520,328	7,633,070
Common stock, shares outstanding (in shares)	8,520,328	7,633,070
Parent Company
Condensed Balance Sheet Statements, Captions [Line Items]
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	8,520,328	7,633,070
Common stock, shares outstanding (in shares)	8,520,328	7,633,070