Income Taxes - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Current income taxes receivable	$ 79	$ 214
Reduction in deferred tax expense related to loss reserve discounting	42,735
Increase in deferred tax expense related to transitional loss reserve discounting	42,735
Valuation allowance	12,606	$ 9,904
Domestic Tax Authority | Internal Revenue Service (IRS)
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	48,300
Net operating loss carryforwards, subject to expiration	43,300
Net operating loss carryforwards, not subject to expiration	5,000
Net operating loss carryforwards subject to limitations	14,100
State Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 11,900