Annual report pursuant to Section 13 and 15(d)

Long-Term Debt - Redemption Price, Percentage (Detail)

v2.4.1.9
Long-Term Debt - Redemption Price, Percentage (Detail)
 12 Months Ended
Dec. 31, 2014
7.0% Senior Subordinated Notes Due 2022 [Member] | Beginning on July 15, 2017 [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 103.50%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= sah_DebtRedemptionPeriodOneMember
/ us-gaap_LongtermDebtTypeAxis
= sah_SevenPercentSeniorSubordinateNoteDueTwoThousandTwentyTwoMember
7.0% Senior Subordinated Notes Due 2022 [Member] | Beginning on July 15, 2018 [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 102.333%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= sah_DebtRedemptionPeriodTwoMember
/ us-gaap_LongtermDebtTypeAxis
= sah_SevenPercentSeniorSubordinateNoteDueTwoThousandTwentyTwoMember
7.0% Senior Subordinated Notes Due 2022 [Member] | Beginning on July 15, 2019 [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 101.167%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= sah_DebtRedemptionPeriodThreeMember
/ us-gaap_LongtermDebtTypeAxis
= sah_SevenPercentSeniorSubordinateNoteDueTwoThousandTwentyTwoMember
7.0% Senior Subordinated Notes Due 2022 [Member] | Beginning on July 15, 2020 and Thereafter [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 100.00%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= sah_DebtRedemptionPeriodFourAndThereafterMember
/ us-gaap_LongtermDebtTypeAxis
= sah_SevenPercentSeniorSubordinateNoteDueTwoThousandTwentyTwoMember
5.0% Senior Subordinated Notes due 2023 [Member] | Beginning on May 15, 2018 [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 102.50%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= us-gaap_DebtInstrumentRedemptionPeriodOneMember
/ us-gaap_LongtermDebtTypeAxis
= sah_FivePercentSeniorSubordinateNoteDueTwoThousandTwentyThreeMember
5.0% Senior Subordinated Notes due 2023 [Member] | Beginning on May 15, 2019 [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 101.667%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= us-gaap_DebtInstrumentRedemptionPeriodTwoMember
/ us-gaap_LongtermDebtTypeAxis
= sah_FivePercentSeniorSubordinateNoteDueTwoThousandTwentyThreeMember
5.0% Senior Subordinated Notes due 2023 [Member] | Beginning on May 15, 2020 [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 100.833%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= us-gaap_DebtInstrumentRedemptionPeriodThreeMember
/ us-gaap_LongtermDebtTypeAxis
= sah_FivePercentSeniorSubordinateNoteDueTwoThousandTwentyThreeMember
5.0% Senior Subordinated Notes due 2023 [Member] | Beginning on May 15, 2021 and Thereafter [Member]  
Debt Instrument Redemption [Line Items]  
Redemption Price 100.00%us-gaap_DebtInstrumentRedemptionPricePercentage
/ us-gaap_DebtInstrumentRedemptionPeriodAxis
= sah_DebtInstrumentRedemptionPeriodFourAndThereafterMember
/ us-gaap_LongtermDebtTypeAxis
= sah_FivePercentSeniorSubordinateNoteDueTwoThousandTwentyThreeMember