Equity - Cash Dividends (Details) - $ / shares													3 Months Ended								12 Months Ended
	Nov. 01, 2019	Sep. 06, 2019	Jun. 20, 2019	Feb. 21, 2019	Nov. 02, 2018	Sep. 07, 2018	Jun. 14, 2018	Feb. 15, 2018	Oct. 27, 2017	Sep. 08, 2017	Jun. 22, 2017	Feb. 16, 2017	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity [Abstract]
Cash dividends declared per common share (in dollars per share)	$ 1.18	$ 1.07	$ 1.07	$ 1.07	$ 1.07	$ 0.96	$ 0.96	$ 0.96	$ 0.71	$ 0.64	$ 0.64	$ 0.64	$ 1.18	$ 1.07	$ 1.07	$ 1.07	$ 1.07	$ 0.96	$ 0.96	$ 0.96	$ 4.39	$ 3.95	$ 2.63