Reinsurance - Effect of Reinsurance Agreements on Premiums Written and Earned (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Net premiums written | |||||||||||
| Direct | $ 376,052 | $ 287,791 | $ 202,586 | ||||||||
| Ceded | (43,400) | (30,988) | (28,914) | ||||||||
| Net premiums written | 332,652 | 256,803 | 173,672 | ||||||||
| Net premiums earned | |||||||||||
| Direct | 398,303 | 292,064 | 192,326 | ||||||||
| Ceded | (53,288) | (40,867) | (26,586) | ||||||||
| Net premiums earned | $ 95,517 | $ 92,381 | $ 83,249 | $ 73,868 | $ 69,261 | $ 65,407 | $ 61,615 | $ 54,914 | $ 345,015 | $ 251,197 | $ 165,740 |