Subordinated Debt Securities (Summary of the Nature and Terms of the Junior Subordinated Debt and Trust) (Details) - Junior subordinated debt shares in Thousands, $ in Thousands			12 Months Ended
	Aug. 23, 2007 USD ($) shares	Jun. 21, 2005 USD ($) shares	Dec. 31, 2021 item
Subordinated Borrowing [Line Items]
Interest Payment Extension Period Elected | item			20
Debt to capital ratio covenant			35.00%
Hallmark Statutory Trust I [Member]
Subordinated Borrowing [Line Items]
Issue date		Jun. 21, 2005
Principal amount of trust preferred securities		$ 30,000
Principal amount of junior subordinated debt securities		$ 30,928
Maturity date of junior subordinated debt securities		Jun. 15, 2035
Trust common stock | shares		928
Interest rate, per annum		Three Month LIBOR + 3.25%
Current interest rate			3.45%
Hallmark Statutory Trust I [Member] | London Interbank Offered Rate (LIBOR) [Member]
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate		3.25%
Hallmark Statutory Trust I I [Member]
Subordinated Borrowing [Line Items]
Issue date	Aug. 23, 2007
Principal amount of trust preferred securities	$ 25,000
Principal amount of junior subordinated debt securities	$ 25,774
Maturity date of junior subordinated debt securities	Sep. 15, 2037
Trust common stock | shares	774
Interest rate, per annum	Three Month LIBOR + 2.90%
Current interest rate			3.10%
Hallmark Statutory Trust I I [Member] | London Interbank Offered Rate (LIBOR) [Member]
Subordinated Borrowing [Line Items]
Debt instrument, basis spread on variable rate	2.90%