Fair Value (Narrative) (Details) (USD $)	3 Months Ended
Mar. 31, 2015
Fair value, equity, Level 1 to Level 2 transfers, amount	0
Fair value, equity, Level 2 to Level 1 transfers, amount	0
Collateralized Bank Loan [Member]
Current yield to maturity percentage	9.00%

The fair value of the discounted cash flows using current yield to maturity, which is based on the relevant spread over LIBOR for this particular loan to discount future cash flows.

No definition available.

+ Details

Name:	hall_CurrentYieldToMaturityPercentage
Namespace Prefix:	hall_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of transfers of financial instruments classified in shareholders' equity measured on a recurring basis out of level 1 of the fair value hierarchy into level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bb)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueEquityLevel1ToLevel2TransfersAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of transfers of financial instruments classified in shareholders' equity measured on a recurring basis out of level 2 of the fair value hierarchy into level 1.

+ References

+ Details

Name:	us-gaap_FairValueEquityLevel2ToLevel1TransfersAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CollateralizedDebtObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: