Fair Value (Narrative) (Details)	12 Months Ended
Dec. 31, 2021 security
Fair Value [Abstract]
Available-For-Sale Securities, Number Of Debt Securities With Unobservable Inputs	1

Available-For-Sale Securities, Number Of Debt Securities With Unobservable Inputs

No definition available.

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Namespace Prefix:	hall_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration