Commitments and Contingencies (Details) ₩ in Millions, R$ in Millions, $ in Millions	3 Months Ended		4 Months Ended		12 Months Ended
	Jun. 30, 2017 USD ($)	Jun. 30, 2017 KRW (₩)	Aug. 31, 2021 USD ($)	Aug. 31, 2021 KRW (₩)	Dec. 31, 2017 USD ($)	Dec. 31, 2017 KRW (₩)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 KRW (₩)	Sep. 30, 2021 BRL (R$)	Sep. 30, 2020 USD ($)
Loss Contingencies [Line Items]
Pre-assessment notice, amount			$ 9.0	₩ 10,600.0
Tax Authority, South Korea (SRTO) | Assessment | Foreign Tax Authority
Loss Contingencies [Line Items]
Pre-assessment notice, amount					$ 9.5	₩ 11,300.0	$ 9.9	₩ 11,700.0
Tax Authority, South Korea (SRTO) | Additional Assessment | Foreign Tax Authority
Loss Contingencies [Line Items]
Pre-assessment notice, amount	$ 17.0	₩ 20,100.0
Federal, State and Municipal Tax Authorities in Brazil | Assessment | Foreign Tax Authority
Loss Contingencies [Line Items]
Estimate of possible loss									R$ 57.7	$ 10.7