Nature of Operations and Summary of Significant Accounting Policies - Aircraft Fleet (Details)	12 Months Ended
	Dec. 31, 2023 aircraft
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of daily departures	1,850
Number of aircraft held by entity	603
E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	237
E175 | Minimum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	65
E175 | Maximum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	76
CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	49
CRJ 900 | Minimum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	65
CRJ 900 | Maximum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	76
CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	167
CRJ 700 | Minimum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	65
CRJ 700 | Maximum
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of seats on aircraft	76
CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	150
Number of seats on aircraft	50
United
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	198
Percentage of aggregate capacity operated	40.80%
United | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	90
United | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	19
United | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	89
Delta
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	135
Percentage of aggregate capacity operated	27.80%
Delta | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	85
Delta | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	41
Delta | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	9
American
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	110
Percentage of aggregate capacity operated	22.70%
American | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	20
American | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	90
Alaska
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	42
Percentage of aggregate capacity operated	8.70%
Alaska | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	42
Aircraft in schedule service or under contract
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	485
Aircraft in schedule service or under contract | E175
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	237
Aircraft in schedule service or under contract | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	41
Aircraft in schedule service or under contract | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	118
Aircraft in schedule service or under contract | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	89
SWC
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	16
SWC | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	16
Number of seats on aircraft	30
Leased to third parties
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	40
Leased to third parties | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	5
Leased to third parties | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	35
Other
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	62
Other | CRJ 900
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	3
Other | CRJ 700
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	14
Other | CRJ 200
Nature of Operations and Summary of Significant Accounting Policies [Line Items]
Number of aircraft held by entity	45