CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends per common share (in dollars per share)	$ 0.96	$ 0.94	$ 0.88
Awards under LTIP (in dollars per share)	$ 0.96	$ 0.94	$ 0.44

Per-share or per-unit amount of incentive dividend declared and paid to managing member or general partner.

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