Investments - Aggregate Fair Value and Gross Unrealized Loss in Continuous Unrealized Loss Position (Details)	Jun. 30, 2020 USD ($) security	Dec. 31, 2019 USD ($) security	Jun. 30, 2019 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Gross unrealized posisiton	$ 0
Fair Value
Less Than 12 Months		$ 3,387,000
12 Months or Longer		0
Total		3,387,000
Unrealized Loss
Less Than 12 Months		(8,000)
12 Months or Longer		0
Total		(8,000)
Credit losses recognized in earnings	0		$ 0
Available-for-sale securities	$ 10,198,000	$ 9,306,000
Number of securities in unrealized loss position for less than 12 months | security	0	5
Number of securities in unrealized loss position for more than 12 months | security	0	0
Municipal bonds
Fair Value
Less Than 12 Months		$ 3,387,000
12 Months or Longer		0
Total		3,387,000
Unrealized Loss
Less Than 12 Months		(8,000)
12 Months or Longer		0
Total		$ (8,000)
Number of portfolio securities | security	9	8
Available-for-sale securities	$ 4,363,000	$ 3,370,000
Agency mortgage-backed securities
Unrealized Loss
Number of portfolio securities | security	14	13
Available-for-sale securities	$ 5,835,000	$ 5,936,000