Debt and Other Obligations (Tables)

6 Months Ended

Jun. 30, 2018

Debt Disclosure [Abstract]

Schedule of Long-term Debt

Long-term debt is comprised of the following:

	As of				Three Months Ended June 30,				Six Months Ended June 30,
	June 30, 2018		December 31, 2017		2018		2017		2018		2017
	(in millions)				(weighted-average interest rates)
Fixed-rate senior term loans due through 2027	$	400.3	$	417.9	4.10	%	4.10	%	4.10	%	4.10	%
Fixed-rate junior term loans due through 2022	35.3		39.3		6.90	%	6.90	%	6.90	%	6.90	%
Fixed-rate loans due through 2029	502.0		518.0		3.83	%	3.82	%	3.83	%	3.82	%
Fixed-rate class A 2015-1 EETC due through 2028	393.6		408.6		4.10	%	4.10	%	4.10	%	4.10	%
Fixed-rate class B 2015-1 EETC due through 2024	84.0		92.0		4.45	%	4.45	%	4.45	%	4.45	%
Fixed-rate class C 2015-1 EETC due through 2023	115.2		—		4.93	%	N/A		4.93	%	N/A
Fixed-rate class AA 2017-1 EETC due through 2030	190.0		37.5		3.38	%	N/A		3.38	%	N/A
Fixed-rate class A 2017-1 EETC due through 2030	63.3		12.5		3.65	%	N/A		3.65	%	N/A
Fixed-rate class B 2017-1 EETC due through 2026	70.0		13.8		3.80	%	N/A		3.80	%	N/A
Fixed-rate class C 2017-1 EETC due through 2023	65.7		—		5.11	%	N/A		5.11	%	N/A
Long-term debt	1,919.4		1,539.6
Less current maturities	145.9		115.4
Less unamortized discounts	41.7		36.7
Total	$	1,731.8	$	1,387.5

Schedule of Maturities of Long-term Debt

At June 30, 2018, long-term debt principal payments for the next five years and thereafter are as follows:

	June 30, 2018
	(in millions)
remainder of 2018	$	76.6
2019	152.5
2020	150.0
2021	147.1
2022	144.0
2023 and beyond	1,249.2
Total debt principal payments	$	1,919.4

Schedule of Interest Expense, Long-term Debt

Interest expense related to long-term debt consisted of the following:

	Three Months Ended June 30,				Six Months Ended June 30,
	2018		2017		2018		2017
	(in thousands)
Senior term loans	$	4,257	$	4,619	$	8,573	$	9,290
Junior term loans	636		775		1,303		1,578
Fixed-rate loans	4,881		1,586		9,792		1,744
Class A 2015-1 EETC	4,015		4,321		8,157		8,629
Class B 2015-1 EETC	930		1,108		1,942		2,292
Class C 2015-1 EETC	789		—		789		—
Class AA 2017-1 EETC	1,576		—		2,257		—
Class A 2017-1 EETC	568		—		814		—
Class B 2017-1 EETC	654		—		936		—
Class C 2017-1 EETC	466		—		466		—
Commitment fees	51		28		103		58
Amortization of debt discounts	1,655		1,290		3,146		2,521
Total	$	20,478	$	13,727	$	38,278	$	26,112