Shareholders' Equity (Tables)

9 Months Ended

Sep. 30, 2017

Shareholders' Equity [Abstract]

Schedule Of Preferred Stock Outstanding

				September 30, 2017			December 31, 2016
		Earliest Potential	Dividend	Shares	Amount		Shares	Amount
Series	Issuance Date	Redemption Date	Rate	Outstanding	(in thousands)		Outstanding	(in thousands)
Series T	May, 2012	May, 2017	6.00%	5,200	$	130,000	14,000	$	350,000
Series U	September, 2012	September, 2017	5.75%	9,200		230,000	9,200		230,000
Series V	March, 2013	March, 2018	5.70%	4,400		110,000	4,400		110,000
Series W	October, 2016	October, 2021	5.20%	7,590		189,750	7,590		189,750
Series X	September, 2017	September, 2022	5.25%	9,200		230,000	—		—
Total				35,590	$	889,750	35,190	$	879,750