XML 59 R44.htm IDEA: XBRL DOCUMENT v3.8.0.1

Commitments and Contingencies - Aircraft Purchase Commitments by AC Type (Details)	Mar. 31, 2018 aircraft
B-737-8 MAX
Unrecorded Unconditional Purchase Obligation [Line Items]
Aircraft Purchase Commitments, Minimum Quantity Required	236
Aircraft Purchase Commitments - Options	115
B-737-7 MAX
Unrecorded Unconditional Purchase Obligation [Line Items]
Aircraft Purchase Commitments, Minimum Quantity Required	30
B-737-800
Unrecorded Unconditional Purchase Obligation [Line Items]
Aircraft Purchase Commitments, Minimum Quantity Required	17

X

- Definition

The amount the company has an option to purchase within the contractual purchase commitment.

+ References

No definition available.

+ Details

Name:	luv_LongTermPurchaseCommitmentsOptions737Mx
Namespace Prefix:	luv_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

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_UnrecordedUnconditionalPurchaseObligationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

+ References

No definition available.

+ Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationMinimumQuantityRequired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	us-gaap_AircraftTypeAxis=luv_B7378MAXMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_AircraftTypeAxis=us-gaap_B737MaxMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_AircraftTypeAxis=us-gaap_B737800Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: