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The fair value adjustment of a derivative asset.

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The amount of governmental assistance due to COVID-19.

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Net Periodic Benefit Cost (Credit), Total

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Amount of realized and unrealized loss of derivative instruments not designated or qualifying as hedging instruments.

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Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement.

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THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES - Other Expense (Details) kr in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2020 SEK (kr)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 SEK (kr)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 SEK (kr)
Other Expense (Income):
Derivative liability fair value adjustment for embedded conversion feature in the Convertible Notes	$ 89.4	kr (89.4)	$ (23.5)	kr 23.5	$ (66.4)	kr 66.4
Derivative asset fair value adjustment for contingent call option related to the Class B common stock purchase and cancellation agreement	19.6	kr (19.6)	17.7	kr (17.7)	(45.0)	kr 45.0
Business interruption insurance recoveries	(0.5)		(1.1)		(0.4)
Credit losses related to contingent lease guarantees	15.0
Governmental assistance due to COVID-19	(38.6)
Loss on Pound sterling forward contract			0.9		0.4
Foreign currency transactions losses	(2.8)		1.5		1.4
Non-operating components of net periodic benefit cost	1.1		1.2		0.8
Gain (loss) on extinguishment or repayment of debt	(93.6)		16.6
Financing fees related to modification of debt	39.3				0.4
Other			0.1		0.7
Other expense (income)	28.9		$ 13.4		$ (108.1)
Second Lien Notes due 2026
Other Expense (Income):
Gain (loss) on extinguishment or repayment of debt	$ (93.6)