Finite lived intangible assets amortization expense remainder of fiscal year and thereafter.

No definition available.

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Namespace Prefix:	mesa_
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Period Type:	instant

- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI https://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

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Period Type:	duration

- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
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- Details

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Period Type:

Intangible Assets - Additional Information (Detail) - USD ($)	3 Months Ended			6 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Impairment loss on intangible assets	$ 16,743,000		$ 39,475,000	$ 20,462,000	$ 39,475,000
Amortization expense recognized	0		$ 300,000	100,000	$ 500,000
Amortization expense for remainder of fiscal year and thereafter	$ 0			$ 0
Customer Relationships [Member] \| American Capacity Purchase Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment loss on intangible assets		$ 3,700,000