Derivatives - Interest Rate Swaps (Details) - USD ($)	1 Months Ended			3 Months Ended												9 Months Ended
	Sep. 30, 2021	May 31, 2021	Dec. 31, 2020	Sep. 30, 2021		Jun. 30, 2021		Mar. 31, 2021		Sep. 30, 2020		Jun. 30, 2020		Mar. 31, 2020		Sep. 30, 2021		Sep. 30, 2020		Apr. 30, 2019
Derivatives
Derivative, notional amount	$ 150,000,000			$ 150,000,000												$ 150,000,000				$ 850,000,000
Derivative, fixed interest rate																				2.28%
Derivative, termination payment	500,000	$ 1,300,000	$ 10,900,000
Derivative, notional amount, amount terminated	100,000,000	$ 100,000,000	500,000,000	100,000,000												100,000,000				$ 700,000,000
Derivative liability	12,700,000			12,700,000												12,700,000
Change in fair value of derivatives due to accelerated amortization				3,500,000												9,500,000
Tax benefit (expense)				(1,200,000)	[1]	$ (1,100,000)		$ (1,100,000)		$ (1,100,000)		$ (500,000)		$ 4,000,000		(3,400,000)		$ 2,400,000
Unrealized gain (loss) on designated cash flow hedge				3,800,000	[1],[2]	$ 3,700,000	[3]	$ 3,600,000	[4]	3,600,000	[1],[5]	$ 1,500,000	[6]	$ (13,100,000)	[7]	11,100,000	[1]	(8,000,000.0)	[1]
Interest expense				5,000,000.0						4,600,000						14,600,000		9,600,000
Interest expense expected to be reclassified out of accumulated other comprehensive income (loss) over the next twelve months	3,700,000			3,700,000												3,700,000
Fair value of derivative liabilities—current	(110,900,000)		(37,100,000)	(110,900,000)												(110,900,000)
Interest rate swaps
Derivatives
Change in fair value of interest rate swaps				5,000,000.0						4,700,000						14,500,000		(10,400,000)
Tax benefit (expense)				(1,200,000)						(1,100,000)						(3,400,000)		2,400,000
Unrealized gain (loss) on designated cash flow hedge				3,800,000						$ 3,600,000						11,100,000		$ (8,000,000.0)
Fair value of derivative liabilities—current	$ (700,000)		$ (7,600,000)	$ (700,000)												$ (700,000)

[1] Includes a tax expense of $1.2 million and a tax expense of $1.1 million for the three months ended September 30, 2021 and 2020, respectively, and a tax expense of $3.4 million and a tax benefit of $2.4 million for the nine months ended September 30, 2021 and 2020, respectively.

[2] Includes a tax expense of $1.2 million.

[3] Includes a tax expense of $1.1 million.

[4] Includes a tax expense of $1.1 million.

[5] Includes a tax expense of $1.1 million.

[6] Includes a tax expense of $0.5 million.

[7] Includes a tax benefit of $4.0 million.