XML 86 R69.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Stockholders' Equity - Narrative (Details) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jan. 21, 2019 shares | Dec. 31, 2018 USD ($) vote $ / shares shares | Dec. 31, 2017 shares | Dec. 31, 2016 shares | Oct. 22, 2018 shares | Feb. 29, 2016 USD ($)
Class of Stock [Line Items] |  |  |  |  |  |
Shares repurchased in association with tax withholdings on the vesting of RSUs (in shares) |  | 30,119 | 32,457 | 94,826 |  |
Class A common stock |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Conversion of common stock (in shares) |  | 1 |  |  |  |
Common stock number of votes | vote |  | 1 |  |  |  |
Amount authorized to be repurchased | $ |  |  |  |  |  | $ 250,000,000
Additional amount authorized to be repurchased |  |  |  |  | 250,000,000 |
Class A common stock | Restricted Stock Units (RSUs) |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Treasury stock acquired, average cost (in dollars per share) | $ / shares |  | $ 112.05 |  |  |  |
Adjustments related to tax withholding for share-based compensation | $ |  | $ 3,400,000 |  |  |  |
Class A common stock | The 2016 Stock Repurchase Authorization |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Remaining authorized repurchase amount | $ |  | $ 233,600,000 |  |  |  |
Class B common stock |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Percentage of Class B common to total common stock subject to automatic conversion |  | 1.00% |  |  |  |
Common stock number of votes | vote |  | 10 |  |  |  |
Subsequent Event | Class B common stock |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Number of shares that were agreed to be converted (in shares) | 1,000,000 |  |  |  |  |
Percent of shares required to be converted by the end of every two years | 15.00% |  |  |  |  |
Stock conversion, term | 2 years |  |  |  |  |
Percent of shares required to be converted by December 31, 2020 | 15.00% |  |  |  |  |
Percent of shares required to be converted by December 31, 2022 | 30.00% |  |  |  |  |
Percent of shares required to be converted by December 31, 2024 | 45.00% |  |  |  |  |

X
- Definition Represents the number of votes per class of common stock. + References No definition available. + Details
Name: | lad_CommonStockNumberOfVotes
Namespace Prefix: | lad_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the number of shares of one class common stock shares convertible into another class of common stock. + References No definition available. + Details
Name: | lad_ConversionOfCommonStockShares
Namespace Prefix: | lad_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Shares To Be Converted + References No definition available. + Details
Name: | lad_NumberOfSharesToBeConverted
Namespace Prefix: | lad_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Shares Converted By The End Of Every Two Years + References No definition available. + Details
Name: | lad_PercentOfSharesConvertedByTheEndOfEveryTwoYears
Namespace Prefix: | lad_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Shares To Be Converted, Tranche One + References No definition available. + Details
Name: | lad_PercentOfSharesToBeConvertedTrancheOne
Namespace Prefix: | lad_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Shares To Be Converted, Tranche Three + References No definition available. + Details
Name: | lad_PercentOfSharesToBeConvertedTrancheThree
Namespace Prefix: | lad_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percent Of Shares To Be Converted, Tranche Two + References No definition available. + Details
Name: | lad_PercentOfSharesToBeConvertedTrancheTwo
Namespace Prefix: | lad_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the percentage number of shares of Class B common stock outstanding representing less than 1% of the total number of shares of common stock outstanding that would be subject to automatic conversion. + References No definition available. + Details
Name: | lad_PercentageOfClassBCommonToTotalCommonStockSubjectToAutomaticConversion
Namespace Prefix: | lad_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Conversion, Term + References No definition available. + Details
Name: | lad_StockConversionTerm
Namespace Prefix: | lad_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Repurchase Program, Additional Authorized Amount + References No definition available. + Details
Name: | lad_StockRepurchaseProgramAdditionalAuthorizedAmount
Namespace Prefix: | lad_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award. + References No definition available. + Details
Name: | us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_ClassOfStockLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer. + References No definition available. + Details
Name: | us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramAuthorizedAmount1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount remaining of a stock repurchase plan authorized. + References No definition available. + Details
Name: | us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
Name: | us-gaap_TreasuryStockAcquiredAverageCostPerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShareRepurchaseProgramAxis=lad_The2016StockRepurchaseAuthorizationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |