Related Parties - 1347 Property Insurance Holdings, Inc (Details) $ / shares in Units, $ in Millions								9 Months Ended	12 Months Ended
	Jul. 24, 2018 USD ($) $ / shares	Mar. 15, 2018 shares	Jan. 02, 2018 USD ($) $ / shares	Nov. 01, 2017 shares	Oct. 25, 2017 USD ($) $ / shares shares	Feb. 24, 2015 USD ($) day $ / shares shares	Mar. 26, 2014 day $ / shares shares	Sep. 30, 2019 shares	Dec. 31, 2018	Sep. 30, 2018 $ / shares
Clause 1, 2 and 3
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)								350,000
Clause 1 and 2
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)								225,000
Clause 2
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)								125,000
Share price (in dollars per share) | $ / shares	$ 12.00									$ 12.00
Clause 3
Related Party Transaction [Line Items]
Share price (in dollars per share) | $ / shares	$ 15.00									15
Affiliated Entity
Related Party Transaction [Line Items]
Equity method investment, ownership percentage								0.00%	0.00%
Management
Related Party Transaction [Line Items]
Stock issued (in shares)				475,428	900,000
Share price (in dollars per share) | $ / shares					$ 7.85
Proceeds from termination of contract | $			$ 0.3
Consideration received on transaction | $	$ 1.0		3.0
Proceeds from sale of equity | $			$ 3.0
Common Stock | Management
Related Party Transaction [Line Items]
Effect on future cash flows | $					$ 7.1
Other shares (in shares)		424,572
Maximum
Related Party Transaction [Line Items]
Share price (in dollars per share) | $ / shares	$ 18.00									$ 18
Fundamental Global Investors, LLC | Kingsway Financial Services, Inc
Related Party Transaction [Line Items]
Ownership percentage (less than at March 31, 2019)								5.00%	5.00%
1347 Property Insurance Holdings, Inc.
Related Party Transaction [Line Items]
Preferred stock, dividend rate			8.00%			8.00%
1347 Property Insurance Holdings, Inc. | Clause 2
Related Party Transaction [Line Items]
Share price (in dollars per share) | $ / shares						$ 15.00
1347 Property Insurance Holdings, Inc. | Affiliated Entity
Related Party Transaction [Line Items]
Effect on future cash flows | $						$ 2.0
Stock issued (in shares)						3,000,000
Stock reserved for future issuances (in shares)						100,000
Share price (in dollars per share) | $ / shares			$ 10.00			$ 10.00
Threshold trading days | day						20
Threshold consecutive trading days						30 days
1347 Property Insurance Holdings, Inc. | Affiliated Entity | Clause 1, 2 and 3
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)							375,000
1347 Property Insurance Holdings, Inc. | Affiliated Entity | Clause 1 and 2
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)							250,000
1347 Property Insurance Holdings, Inc. | Affiliated Entity | Clause 2
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)							125,000
Share price (in dollars per share) | $ / shares							$ 15.00
Threshold trading days | day							20
Threshold consecutive trading days							30 days
1347 Property Insurance Holdings, Inc. | Affiliated Entity | Clause 1
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)							125,000
Share price (in dollars per share) | $ / shares							$ 12.00
Threshold trading days | day							20
Threshold consecutive trading days							30 days
1347 Property Insurance Holdings, Inc. | Affiliated Entity | Clause 3
Related Party Transaction [Line Items]
Stock reserved for future issuances (in shares)							125,000
1347 Property Insurance Holdings, Inc. | Common Stock | Affiliated Entity
Related Party Transaction [Line Items]
Other shares (in shares)						1,500,000
1347 Property Insurance Holdings, Inc. | Maximum | Affiliated Entity
Related Party Transaction [Line Items]
Share price (in dollars per share) | $ / shares							$ 18.00
Threshold trading days | day							20
Threshold consecutive trading days							30 days