Pledged Investments (Details Textual) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Securities Available For Sale Pledged Carrying Value	$ 25.9	$ 27.5

The carrying value of available-for-sale securities that serve as collateral for borrowings.

No definition available.

Name:	hall_SecuritiesAvailableForSalePledgedCarryingValue
Namespace Prefix:	hall_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant