XML 54 R42.htm IDEA: XBRL DOCUMENT
v3.21.1

Inventory And Vehicle Floorplan Payable (Components Of Vehicle Floorplan Payable) (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Floorplan Payable [Line Items] |  |
Vehicle floorplan payable | $ 2,298.0 | $ 2,759.9
Trade [Member] |  |
Floorplan Payable [Line Items] |  |
Vehicle floorplan payable | 1,285.2 | 1,541.7
Non-Trade [Member] |  |
Floorplan Payable [Line Items] |  |
Vehicle floorplan payable | $ 1,012.8 | $ 1,218.2

X
- Definition Floorplan Payable [Line Items] + References No definition available. + Details
Name: | an_FloorplanPayableLineItems
Namespace Prefix: | an_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amounts borrowed to finance the purchase of specific new vehicle inventories with the corresponding manufacturers' captive finance subsidiaries ("trade lenders") and specific new and, to a lesser extent, used vehicle inventories with non-trade lenders (lenders that are not captive finance subsidiaries of the manufacturer). + References No definition available. + Details
Name: | an_VehicleFloorplanPayable
Namespace Prefix: | an_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | an_FloorplanPayableAxis=an_TradeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | an_FloorplanPayableAxis=an_NonTradeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |