XML 51 R19.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Schedule II Valuation of Qualifying Accounts and Reserves | 12 Months Ended
--- | ---
Dec. 31, 2012
Schedule II Valuation and Qualifying Accounts and Reserves [Abstract] |
Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] |
SCHEDULE II VALUATION AND QUALIFYING ACCOUNTS AND RESERVES (In Thousands, Except Per Share Data)
Column A |  | Column B |  | Column C |  | Column D |  | Column E
|  |  |  | Charges To |  |  |  |
|  | Balance At |  | Cost |  |  |  |  |  | Balance
|  | Beginning |  | And |  | Other |  |  |  | At End
Description |  | of Period |  | Expense |  | Accounts |  | Deductions |  | of Period
Allowance for doubtful accounts: |  |  |  |  |  |  |  |  |  |
Year ended December 31, 2012 |  | $ | 791 |  |  | $ | 205 |  |  | $ | — |  |  | $ | 167 |  |  | $ | 829 |
Year ended December 31, 2011 |  | 775 |  |  | 83 |  |  | — |  |  | 67 |  |  | 791 |
Year ended December 31, 2010 |  | 775 |  |  | 3 |  |  | — |  |  | 3 |  |  | 775 |

X
- Details
Name: | htld_ScheduleIiValuationAndQualifyingAccountsAndReservesAbstract
Namespace Prefix: | htld_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition No authoritative reference available. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 09 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690 + Details
Name: | us-gaap_ScheduleOfValuationAndQualifyingAccountsDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration