Share Capital - Dividends on Preferred Shares (Details) - USD ($) $ in Thousands			1 Months Ended	12 Months Ended
	Nov. 21, 2018	Jun. 28, 2018	Feb. 21, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Class of Stock [Line Items]
Total Dividends Paid in 2019				$ 35,914	$ 12,133	$ 0
Series D Preferred Shares
Class of Stock [Line Items]
Dividend rate				7.00%
Total Dividends Paid in 2019				$ 28,000	$ 12,100
Series E Preferred Shares
Class of Stock [Line Items]
Dividend rate				7.00%
Total Dividends Paid in 2019				$ 7,900
Public Stock Offering | Series D Preferred Shares
Class of Stock [Line Items]
Dividend rate		7.00%
Public Stock Offering | Series E Preferred Shares
Class of Stock [Line Items]
Dividend rate	7.00%
LIBOR | Public Stock Offering | Series D Preferred Shares
Class of Stock [Line Items]
Basis spread on variable rate		4.015%
Subsequent Event | Series D Preferred Shares
Class of Stock [Line Items]
Total Dividends Paid in 2019			$ 7,000
Subsequent Event | Series E Preferred Shares
Class of Stock [Line Items]
Total Dividends Paid in 2019			$ 1,900