Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Sep. 01, 2016	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred share issuance costs (Series J redemption)		$ (7,408)	$ 0	$ (7,408)	$ 0
Series J Preferred Stock | Redeemable Preferred Stock
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred Stock Dividend Rate Percentage	6.875%
Preferred Stock Redemption Price Per Share	$ 25
Preferred Stock, Redemption Amount	$ 246,250
Preferred share issuance costs (Series J redemption)				$ 7,408