CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Common shares, par value	$ 0.10	$ 0.10
Common shares, shares authorized	300,000,000	300,000,000
Common shares, shares issued	211,095,870	193,995,499
Treasury at cost	254,298	898,267
Class A Cumulative Redeemable Preferred Shares [Member]
Cumulative redeemable preferred shares, liquidation value	$ 500	$ 500
Cumulative redeemable preferred shares, shares authorized	750,000	750,000
Cumulative redeemable preferred shares, shares issued	350,000	350,000
Cumulative redeemable preferred shares, shares outstanding	350,000	350,000
Preferred stock dividend rate	6.375%	6.375%
Cumulative redeemable preferred shares, par value
Class K Cumulative Redeemable Preferred Shares [Member]
Cumulative redeemable preferred shares, liquidation value		$ 500
Cumulative redeemable preferred shares, shares authorized		750,000
Cumulative redeemable preferred shares, shares issued		300,000
Cumulative redeemable preferred shares, shares outstanding		300,000
Preferred stock dividend rate		6.25%
Cumulative redeemable preferred shares, par value