Accounting Policies (Narrative) (Details) $ in Thousands			3 Months Ended	12 Months Ended
	Aug. 23, 2007 USD ($)	Jun. 21, 2005 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)
Number of Reportable Segments | segment				3
Amortized				$ 165,600	$ 141,000
Deferred Policy Ceded Commission, Acquisition Cost				79,000	160,800
Amortized, Ceded				(86,700)	(153,700)
Net				5,200	(8,700)
Deferred, dispositions				(152,700)	(156,800)
Impairment of goodwill			$ 44,700		0
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)			$ 1,300
Goodwill				0	44,695
Property and equipment, gross				$ 36,300	34,600
Property and equipment, depreciation method				straight-line method
Depreciation				$ 3,300	3,000
Property and equipment, accumulated depreciation				27,100	23,800
Policy fees				7,200	8,700
Operating lease right-of-use assets				$ 13,986	$ 16,044
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]				Other Assets	Other Assets
Total operating lease liability				$ 15,862	$ 17,347
Operating Lease, Liability, Statement of Financial Position [Extensible List]				Accounts Payable and Accrued Liabilities	Accounts Payable and Accrued Liabilities
Hallmark Statutory Trust I [Member]
Proceeds from issuance of trust preferred securities		$ 30,000
Hallmark Statutory Trust II [Member]
Proceeds from issuance of trust preferred securities	$ 25,000
Minimum [Member]
Property and equipment, estimated useful lives				3 years	3 years
Maximum [Member]
Property and equipment, estimated useful lives				10 years	10 years
Accounting Standards Update 2016-02 [Member] | Leaseholds and Leasehold Improvements [Member]
Property and equipment, gross				$ 2,900	$ 3,400
Senior unsecured notes due 2029 [Member]
Long-term debt, gross				49,100	49,100
Notes Payable, Fair Value Disclosure				54,300	49,800
Subordinated Debt [Member]
Trust preferred securities, fair value				26,600	41,700
Trust preferred securities, carrying value				$ 55,900	$ 55,900
Subordinated Debt [Member] | Hallmark Statutory Trust I [Member]
Payments to acquire trust preferred investments		$ 30,900
Subordinated Debt [Member] | Hallmark Statutory Trust II [Member]
Payments to acquire trust preferred investments	$ 25,800