Basis of Presentation (Narrative) (Details) - USD ($) $ in Thousands				3 Months Ended
	Jan. 01, 2018	Aug. 23, 2007	Jun. 21, 2005	Mar. 31, 2019
Variable Interest Entity [Line Items]
Reclassification out of AOCI as a result of Tax Act	$ (2,600)
Right-of-use assets				$ 17,713
Lease liabilities				17,972
Revolving Credit Facility B [Member]
Variable Interest Entity [Line Items]
Credit facility, amount outstanding				30,000
Credit facility, fair value				30,200
Hallmark Statutory Trust I [Member]
Variable Interest Entity [Line Items]
Proceeds from issuance of trust preferred securities			$ 30,000
Hallmark Statutory Trust II [Member]
Variable Interest Entity [Line Items]
Proceeds from issuance of trust preferred securities		$ 25,000
Subordinated Debt [Member]
Variable Interest Entity [Line Items]
Trust preferred securities, carrying value				55,800
Trust preferred securities, fair value				$ 44,500
Current yield to maturity percentage				8.00%
Subordinated Debt [Member] | Hallmark Statutory Trust I [Member]
Variable Interest Entity [Line Items]
Payments to acquire trust preferred investments			$ 30,900
Subordinated Debt [Member] | Hallmark Statutory Trust II [Member]
Variable Interest Entity [Line Items]
Payments to acquire trust preferred investments		$ 25,800