Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - $ / shares	3 Months Ended				12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Cash dividends declared per preferred share (in $ per share)	$ 1.8125	$ 1.8125	$ 1.8125	$ 1.8125	$ 7.25	$ 7.25	$ 7.25
Cash dividends declared per common share (in $ per share)	$ 0.67	$ 0.67	$ 0.55	$ 0.55	$ 2.44	$ 2	$ 1.8