Long-Term Debt - Debt (Details)	3 Months Ended							4 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2017 USD ($) $ / shares	Mar. 31, 2016 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2021 USD ($) payment shares $ / shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 11, 2021 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Debt Instrument [Line Items]
Long-term debt									$ 308,129,000	$ 245,053,000
Less current maturities of long-term debt									(3,107,000)	(5,612,000)
Long-term debt of current maturities									305,022,000	239,441,000
Proceeds from Issuance of Warrants							$ 12,376,000
Lifetime to date - Accretion Expense									5,347,000	1,813,000
Remaining Accretion									11,275,000
Loss (gain) on debt extinguishment including debt finance charges and associated fees	$ 10,131,000	$ 709,000	$ 761,000	$ 6,599,000				$ 761,000	9,422,000	(7,360,000)	$ (6,165,000)
Convertible Subordinated Debt | Convertible Senior Notes at 5.00% February 2021
Debt Instrument [Line Items]
Debt Instrument, Face Amount							$ 150,000,000		1,250,000	1,250,000
Long-term debt									0	1,242,000
Debt Instrument, Unamortized Discount									0	(7,000)
Debt Instrument, Fee Amount, Net Balance Shown as a Liability									0	(1,000)
Debt Instrument, Net Carrying Amount									0	1,242,000
Convertible due 2021 - Bond Hedge, Fair Value at Issuance									$ 27,975,000
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares									$ 22.4175
Debt Instrument, Hedge Options			62,341		138,182		300,000	62,341			138,182
Debt Instrument, Warrants Issued and Outstanding					3,860,624		9,007,380		856,920		3,860,624
Debt Instrument, Repurchase Amount			$ 24,466,000					$ 24,466,000					$ 16,000,000
Effective Interest Rate									11.10%
Interest rate (as a percent)									5.00%
Debt Instrument, Fee Amount															$ 5,966,000
Debt Instrument, Increase, Accrued Interest									$ 8,000	1,632,000
Convertible Subordinated Debt | Convertible Senior Notes at 4.50% February 2022
Debt Instrument [Line Items]
Effective Interest Rate									10.90%
Convertible Subordinated Debt | Convertible Senior Notes at 5.00% February 2024
Debt Instrument [Line Items]
Debt Instrument, Face Amount									$ 72,909,000	72,909,000
Long-term debt									72,140,000	62,984,000
Debt Instrument, Unamortized Discount									0	(8,888,000)
Debt Instrument, Fee Amount, Net Balance Shown as a Liability									(769,000)	(1,037,000)
Debt Instrument, Net Carrying Amount									$ 72,140,000	62,984,000
Debt Instrument, Loss on Exchange					$ 5,885,000
Effective Interest Rate									8.77%
Interest rate (as a percent)									5.00%
Percent of the Applicable Conversion Price									130.00%
Last Reported Sales Price Period, Common Stock									20 days
Debt Instrument, Convertible, Threshold Consecutive Trading Days									30
Convertible Senior Notes, Percentage of Principal Required for Repurchase									100.00%
Convertible Debt, Conversion Rate of Commmon Shares, Principal									$ 1,000
Debt Instrument, Convertible, Threshold Trading Days									10
Business Day Period									5 days
Percent of the Product of the Last Reported Sale Price, Common Shares									98.00%
Convertible Preferred Stock, Shares Issued upon Conversion | shares									67.6819
Initial conversion price | $ / shares									$ 14.78
Debt Instrument, Fee Amount					$ 1,394,000						$ 1,394,000
Debt Instrument, Increase, Accrued Interest									$ 3,645,000	3,646,000
Convertible Subordinated Debt | Series II Convertible Senior Notes at 5.00% November 2024
Debt Instrument [Line Items]
Debt Instrument, Face Amount									79,222,000	75,688,000
Long-term debt									78,251,000	64,919,000
Debt Instrument, Unamortized Discount									0	(9,461,000)
Debt Instrument, Fee Amount, Net Balance Shown as a Liability									(971,000)	(1,308,000)
Debt Instrument, Net Carrying Amount									$ 78,251,000	64,919,000
Debt Instrument, Loss on Exchange				$ 6,599,000
Effective Interest Rate									10.40%
Interest rate (as a percent)									5.00%
Percent of the Applicable Conversion Price									130.00%
Last Reported Sales Price Period, Common Stock									20 days
Debt Instrument, Convertible, Threshold Consecutive Trading Days									30
Convertible Senior Notes, Percentage of Principal Required for Repurchase									100.00%
Convertible Debt, Conversion Rate of Commmon Shares, Principal									$ 1,000
Debt Instrument, Convertible, Threshold Trading Days									10
Business Day Period									5 days
Percent of the Product of the Last Reported Sale Price, Common Shares									98.00%
Convertible Preferred Stock, Shares Issued upon Conversion | shares									67.6819
Initial conversion price | $ / shares									$ 14.78
Debt Instrument, Fee Amount										1,505,000
Debt Instrument, Increase, Accrued Interest									$ 3,693,000	2,123,000
Convertible Subordinated Debt | Convertible Senior Notes at 4.25% March 2026
Debt Instrument [Line Items]
Debt Instrument, Face Amount									125,000,000
Long-term debt									119,036,000	0
Debt Instrument, Fee Amount, Net Balance Shown as a Liability									(5,964,000)
Debt Instrument, Net Carrying Amount									$ 119,036,000
Effective Interest Rate									5.40%
Interest rate (as a percent)									4.25%
Percent of the Applicable Conversion Price									130.00%
Last Reported Sales Price Period, Common Stock									20 days
Debt Instrument, Convertible, Threshold Consecutive Trading Days | payment									30
Convertible Senior Notes, Percentage of Principal Required for Repurchase									100.00%
Convertible Debt, Conversion Rate of Commmon Shares, Principal									$ 1,000
Debt Instrument, Convertible, Threshold Trading Days | payment									10
Business Day Period									5 days
Percent of the Product of the Last Reported Sale Price, Common Shares									98.00%
Convertible Preferred Stock, Shares Issued upon Conversion | shares									94.6096
Initial conversion price | $ / shares									$ 10.57
Debt Instrument, Fee Amount												$ 7,305,000
Debt Instrument, Increase, Accrued Interest									$ 4,220,000
Cap Price of Capped Call Transaction | $ / shares									$ 16.58
Capped Call Options, Outstanding | shares									125,000
Convertible Subordinated Debt | Convertible Senior Notes at 4.50% February 2022
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 120,000,000			$ 2,650,000	81,500,000
Long-term debt									2,642,000	73,869,000
Debt Instrument, Unamortized Discount									0	(6,772,000)
Debt Instrument, Fee Amount, Net Balance Shown as a Liability									(8,000)	(859,000)
Debt Instrument, Net Carrying Amount									$ 2,642,000	73,869,000
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares						$ 21.4375
Proceeds from Issuance of Warrants						$ 14,100,000
Debt Instrument, Hedge Options									120,000
Debt Instrument, Hedge Options available for exercise									2,650
Class of Warrant or Right, Outstanding | shares									7,393,141
Debt Instrument, Repurchase Amount		78,850,000
Debt Instrument, Loss on Exchange		$ 709,000
Effective Interest Rate									5.40%
Interest rate (as a percent)									4.50%
Percent of the Applicable Conversion Price									130.00%
Last Reported Sales Price Period, Common Stock									20 days
Debt Instrument, Convertible, Threshold Consecutive Trading Days									30
Convertible Senior Notes, Percentage of Principal Required for Repurchase									100.00%
Convertible Debt, Conversion Rate of Commmon Shares, Principal									$ 1,000
Debt Instrument, Convertible, Threshold Trading Days									10
Business Day Period									5 days
Percent of the Product of the Last Reported Sale Price, Common Shares									98.00%
Convertible Preferred Stock, Shares Issued upon Conversion | shares									61.6095
Initial conversion price | $ / shares									$ 16.23
Debt Instrument, Fee Amount														$ 4,711,000
Debt Instrument, Increase, Accrued Interest									$ 859,000	4,404,000
Other obligations
Debt Instrument [Line Items]
Long-term debt									36,060,000	42,039,000
Revolving Credit Facility | Line of Credit | Revolving Credit and Security Agreement (New Credit Agreement) [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Foreign Currency Fair Value of Amount Outstanding (France)									7,366,000	7,636,000
Letters of credit outstanding									$ 22,150,000	20,000,000
Line of Credit, Covenant Compliance, Required Undrawn Balance, Minimum, Percent									11.25%
Revolving Credit Facility | Line of Credit | Revolving Credit and Security Agreement (New Credit Agreement) [Member] | Euro Member Countries, Euro
Debt Instrument [Line Items]
Line of Credit Facility, Foreign Currency Fair Value of Amount Outstanding (France)									$ 6,500,000	$ 6,400,000
Revolving Credit Facility | Line of Credit | Revolving Credit and Security Agreement (North America Credit Agreement)
Debt Instrument [Line Items]
Line of Credit, Covenant Compliance, Required Undrawn Balance, Minimum, Percent									12.50%
Revolving Credit Facility | Line of Credit | Revolving Credit and Security Agreement (Europe Credit Agreement)
Debt Instrument [Line Items]
Line of Credit, Covenant Compliance, Required Undrawn Balance, Minimum, Percent									12.50%