Common and Preferred Shares Common Shares (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares
Cash Dividends Paid [Line Items]
shelf registration effective term	3
Stock Repurchase Program, Number of Shares Authorized to be Repurchased | shares	15,000,000
Common Stock, Dividends, Per Share, Cash Paid	$ 1.5	$ 1.515	$ 4.5
Common Stock, Shares, Issued | shares	82,225,061	81,917,876
Net proceeds from issuance of common shares | $	$ 460	$ 972	$ 305,556
Common stock declared dividends per share	$ 1.50
Stock Repurchase Program, Authorized Amount | $		$ 150,000
Number of common shares repurchased | shares		4,066,716
Treasury Stock, Value, Acquired, Cost Method | $		$ 106,000
Common Stock [Member]
Cash Dividends Paid [Line Items]
Common stock declared dividends per share	1.50	$ 1.515
Total Cash Distribution Per Share [Member] | Common Stock [Member]
Cash Dividends Paid [Line Items]
Common Stock, Dividends, Per Share, Cash Paid	1.2500	1.8900
Taxable Ordinary Income [Member] | Common Stock [Member]
Cash Dividends Paid [Line Items]
Common Stock, Dividends, Per Share, Cash Paid	1.2500	0.8888
Return of Capital [Member] | Common Stock [Member]
Cash Dividends Paid [Line Items]
Common Stock, Dividends, Per Share, Cash Paid	0	0.5634
Long-term Capital Gain [Member] | Common Stock [Member]
Cash Dividends Paid [Line Items]
Common Stock, Dividends, Per Share, Cash Paid	0	0.4378
Unrecaptured Section 1250 gain	$ 0	$ 0.1439
direct share purchase plan [Member]
Cash Dividends Paid [Line Items]
Common Stock, Shares, Issued | shares	11,798	36,176
Net proceeds from issuance of common shares | $	$ 600	$ 1,100