XML 23 R70.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Income Taxes - Summary of Changes in Liability Related to Unrecognized Tax Benefits (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
--- | --- | --- | --- | ---
Schedule Of Unrecognized Tax Benefits [Line Items] |  |  |  |
Accrued interest and penalties | $ 1.2 us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued | $ 1.1 us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued | $ 2.4 us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued | $ 4.9 us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued
State and Local Jurisdiction [Member] |  |  |  |
Schedule Of Unrecognized Tax Benefits [Line Items] |  |  |  |
Net operating losses | $ 0.8 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember | $ 1.0 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember | $ 1.3 us-gaap_OperatingLossCarryforwards / us-gaap_IncomeTaxAuthorityAxis = us-gaap_StateAndLocalJurisdictionMember |

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

X
- Definition The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319 + Details
Name: | us-gaap_IncomeTaxExaminationPenaltiesAndInterestAccrued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319 + Details
Name: | us-gaap_OperatingLossCarryforwards
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |