Financial Commitments (Narrative) (Details)		12 Months Ended
	Aug. 18, 2020 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2023 USD ($)	Mar. 31, 2022	Jun. 15, 2021 USD ($)	Aug. 19, 2020 USD ($)	Apr. 20, 2017 USD ($)	Jun. 15, 2016 USD ($)
Debt Instrument [Line Items]
Loss on debt extinguishment			$ 7,100,000
Remaining principal balance		$ 1,010,763,000
Initial conversion rate		0.0330579
Loan outstanding		$ 993,654,000	1,025,465,000
BMO Harris Bank
Debt Instrument [Line Items]
Increase in applicable margin on overdue amounts upon default	2.00%
Credit Facility 2020
Debt Instrument [Line Items]
Loan outstanding		$ 27,000,000	0
Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Net leverage ratio (maximum)	2.75
Weighted-average annual interest rate on borrowings		6.50%
Amount outstanding		$ 27,000,000
Available borrowing capacity		148,000,000
First Lien | BMO Harris Bank
Debt Instrument [Line Items]
Net leverage ratio (maximum)	1.35
Forecast | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Net leverage ratio (maximum)						2.25
Line of Credit | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 425,000,000
Initial principal amount installment percentage	0.25%
Unsecured Debt | BMO Harris Bank
Debt Instrument [Line Items]
Fixed charge coverage ratio (maximum)	2.00
Convertible Notes
Debt Instrument [Line Items]
Face amount										$ 200,000,000
Interest rate (as a percent)										2.875%
Repurchased face amount								$ 130,100,000
Aggregate repurchase price								$ 132,400,000
Remaining principal balance			69,918,000				$ 69,900,000
Loan outstanding		0	67,878,000
Convertible Notes | Equity Component
Debt Instrument [Line Items]
Unamortized debt issuance costs			1,543,000
Conversion feature			46,800,000	$ 46,800,000
Convertible Notes | Liability Component
Debt Instrument [Line Items]
Unamortized debt issuance costs			5,051,000
Face amount			69,918,000	200,000,000
Issuance of convertible notes				$ 153,200,000
2017 Senior Notes | 2017 Senior Notes
Debt Instrument [Line Items]
Remaining principal balance		500,000,000	500,000,000
Loan outstanding		$ 496,244,000	495,271,000
2017 Senior Notes | Private Placement | 2017 Senior Notes
Debt Instrument [Line Items]
Face amount									$ 500,000,000
Interest rate (as a percent)									6.875%
Redemption price, change of control triggering event (as a percent)		101.00%
Equipment Financing Loans
Debt Instrument [Line Items]
Loan outstanding		$ 41,700,000	36,900,000
Term of debt		5 years
Mortgages
Debt Instrument [Line Items]
Interest rate (as a percent)		2.25%
Loan outstanding		$ 14,600,000	10,700,000
Term of debt		10 years
Mortgages | Forecast
Debt Instrument [Line Items]
Balloon payments					$ 6,800,000
Minimum | Equipment Financing Loans
Debt Instrument [Line Items]
Interest rate (as a percent)		2.54%
Maximum | Equipment Financing Loans
Debt Instrument [Line Items]
Interest rate (as a percent)		3.89%
Credit Facility | Credit Facility 2020
Debt Instrument [Line Items]
Unamortized debt issuance costs		$ 2,100,000	$ 2,600,000
Credit Facility | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Increase in line of credit allowed amount	$ 173,500,000
Accordion feature percentage of LTM EBITDA	50.00%
Credit Facility | Line of Credit | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 175,000,000
Letters Of Credit | Line of Credit | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	75,000,000
Bridge Loan | Line of Credit | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 10,000,000
Secured Debt | Unsecured Debt | BMO Harris Bank | Junior Lien
Debt Instrument [Line Items]
Total net leverage ratio (maximum)	3.50
Federal Funds Rate | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	0.50%
LIBOR | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	4.75%
LIBOR | Credit Agreement 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	1.00%
LIBOR | Term Loan B | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	4.75%
LIBOR | Mortgages
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))		3.00%
LIBOR | Minimum | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	4.25%
LIBOR | Minimum | Term Loan B | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	4.50%
LIBOR | Maximum | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	4.75%
LIBOR | Maximum | Term Loan B | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	4.75%
Base Rate | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	3.75%
Base Rate | Term Loan B | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	3.75%
Base Rate | Minimum | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	3.25%
Base Rate | Minimum | Term Loan B | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	3.50%
Base Rate | Maximum | Credit Facility 2020 | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	3.75%
Base Rate | Maximum | Term Loan B | BMO Harris Bank
Debt Instrument [Line Items]
Basis points added to reference rate (as a percent))	3.75%