Preferred Shares - Dividends (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 02, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Equity [Abstract]
Deemed dividend on beneficial conversion feature at April 2, 2018	$ 47,800	$ 0	$ 0	$ 47,849
In-kind dividends		1,887	1,849	1,459
Deemed dividend on beneficial conversion feature related to in-kind dividend		0	0	281
Deemed dividend on beneficial conversion feature related to in-kind dividend		$ 1,887	$ 1,849	$ 49,589