Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
	Jan. 01, 2018	Dec. 31, 2019	Dec. 31, 2018
Summary of Significant Accounting Policies [Line Items]
Adjustment retained earnings		$ (211,533)	$ (192,319)
Deferred tax asset contract liability		2,543	3,242
Valuation allowance		6,330	457
Flight equipment cost			45,896
Accumulated depreciation			5,851
Flight equipment cost, net			40,045
Contingent variable revenue			57,252
Depreciation expense		23,578	20,363
Accrued payment of interest and penalties		121	252
Amortization of contract liabilities		(3,725)	(3,480)
Deferred tax asset		26,894	18,852
Loss from Operations		(20,862)	$ (24,498)
Revenue from Contract with Customer, Product and Service Benchmark [Member]
Summary of Significant Accounting Policies [Line Items]
Contract Revenues Purchase Agreement, Percent			100.00%
Accounting Standards Update (ASU) 2014-09 [Member]
Summary of Significant Accounting Policies [Line Items]
Contract liability			$ 15,235
Contract assets			$ 1,668
United Airlines [Member] | Revenue from Contract with Customer, Product and Service Benchmark [Member]
Summary of Significant Accounting Policies [Line Items]
Contract Revenues Purchase Agreement, Percent			97.20%
United Airlines [Member] | Accounting Standards Update (ASU) 2014-09 [Member]
Summary of Significant Accounting Policies [Line Items]
Contract liability		5,539	$ 4,999
American Airlines [Member] | Revenue from Contract with Customer, Product and Service Benchmark [Member]
Summary of Significant Accounting Policies [Line Items]
Contract Revenues Purchase Agreement, Percent			2.80%
Revision of Prior Period, Change in Accounting Principle, Adjustment [Member]
Summary of Significant Accounting Policies [Line Items]
Loss from Operations			$ (6,359)
Revision of Prior Period, Change in Accounting Principle, Adjustment [Member] | Accounting Standards Update (ASU) 2014-09 [Member]
Summary of Significant Accounting Policies [Line Items]
Adjustment retained earnings	$ 5,420
Deferred tax asset contract liability			1,788
Additional aircraft for service			9,439
Additional amortization expense			400
Upfront costs			3,480
Adjustments operating income			(6,359)
Valuation allowance			457
Contract liability	9,725		15,235
Upfront costs	$ 2,068
Amortization of contract liabilities		3,725	3,480
Upfront costs amortized		$ 400	400
Contract assets			1,668
Deferred contract liability			6,200
Deferred tax asset			1,284
Loss from Operations			$ 6,359