CONDENSED CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018
Statement of Stockholders' Equity [Abstract]
Dividends on Common Shares (in dollars per share)	$ 0.535	$ 0.535	$ 0.505	$ 0.505
Issuance of Common Shares, par value (in dollars per share)	$ 5