Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Legal Fees
Related Party Transaction
Amounts of Transactions		$ 717		$ 1,425
Spouse of Executive Officer | Legal Fees
Related Party Transaction
Amounts of Transactions		359		713
Related party interest in billings (percentage)					50.00%
Director | AmRisc gross written premiums
Related Party Transaction
Amounts of Transactions	$ 163,045,000	127,757	$ 270,663,000	221,763
Related party interest in billings (percentage)			7.70%
Director | AmRisc Fees and Commission
Related Party Transaction
Amounts of Transactions	46,014,000	34,737	$ 74,993,000	59,166
Director | AmRisc ceded premiums written
Related Party Transaction
Amounts of Transactions	$ 2,333,000	$ 1,805	3,878,000	$ 3,366
Director | AmRisc net premiums receivable
Related Party Transaction
Amounts of Transactions			$ 71,356