Amazon - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended		6 Months Ended		12 Months Ended
	Jan. 01, 2020	Mar. 31, 2019	May 31, 2016	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2018	Dec. 31, 2019
Class Of Warrant Or Right [Line Items]
Revenues				$ 825,253	$ 663,918	$ 1,468,755	$ 1,343,601
Percentage of customer warrant liability	60.00%
Warrant liability unrealized (gains) losses				30,700	(42,300)	29,700	4,300
Fair value of warrant liability				39,500		39,500			$ 24,300
Amortization of customer incentive asset				$ 9,500	$ 6,900	$ 18,556	$ 13,200
Warrant A [Member]
Class Of Warrant Or Right [Line Items]
Right to acquire outstanding common shares						up to 20% of our outstanding common shares
Warrant exercise price			$ 37.34
Warrant for number of shares fully vested								7,500,000
Warrant vesting year			2021-05
Warrants exercised						0
Exercise price of warrants exercisable			$ 37.34
Warrant B [Member]
Class Of Warrant Or Right [Line Items]
Warrant exercise price			37.34
Warrants exercised						0
Additional warrant to acquire outstanding shares						up to an additional 10% of our outstanding common shares
Exercise price of warrants exercisable			$ 37.34
Additional warrant to buy number of shares vesting			3,770,000
Vesting increments of Amazon warrants			37,660
Revenues			$ 4,200
Warrant vested				225,690		225,690
Additional warrant vesting year			2023-05
Warrant C [Member]
Class Of Warrant Or Right [Line Items]
Right to acquire outstanding common shares						up to an additional 9.9% of our outstanding common shares
Warrant exercise price		$ 52.67
Warrant vesting year						2026-03
Exercise price of warrants exercisable		$ 52.67
Vesting increments of Amazon warrants		45,623
Revenues		$ 6,900
Warrant vested				0		0
Incremental warrant to buy number of shares vesting.		6,660,000
Warrant A, B and C [Member]
Class Of Warrant Or Right [Line Items]
Right to acquire outstanding common shares						up to a total of 39.9% (after the issuance) of our outstanding common shares
Maximum [Member]
Class Of Warrant Or Right [Line Items]
Amazon entitled to vote shares of it owns of outstanding common shares percentage		14.90%
Maximum [Member] | Warrant A [Member]
Class Of Warrant Or Right [Line Items]
Warrant providing right to acquire outstanding common shares percentage			20.00%
Maximum [Member] | Warrant B [Member]
Class Of Warrant Or Right [Line Items]
Percentage of additional warrant to acquire outstanding common shares			10.00%
Revenues			$ 420,000
Maximum [Member] | Warrant C [Member]
Class Of Warrant Or Right [Line Items]
Warrant providing right to acquire outstanding common shares percentage		9.90%
Revenues		$ 1,000,000
Maximum [Member] | Warrant A, B and C [Member]
Class Of Warrant Or Right [Line Items]
Warrant providing right to acquire outstanding common shares percentage		39.90%
Dry Leases [Member]
Class Of Warrant Or Right [Line Items]
Lease term				10 years		10 years
Percentage of customer warrant liability	40.00%
CMI Operation [Member]
Class Of Warrant Or Right [Line Items]
Lease term		7 years		7 years		7 years
Lease term option to extend		true				true
Lease term of extension		10 years		10 years		10 years
Percentage of customer warrant liability	60.00%