Business Segment Information (Reconciliation Of Segment Margin To (Loss) Income Before Income Taxes) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting [Abstract]
Segment margin	$ 77,351	$ 72,065
Corporate general and administrative expenses	(11,061)	(10,837)
Depreciation and amortization	(19,280)	(15,049)
Interest Income (Expense), Net	(12,804)	(11,441)
Distributable cash from equity investees in excess of equity in earnings	(5,777)	(6,564)
Non-cash items not included in segment margin	3,325	(4,295)
Cash payments from direct financing leases in excess of earnings	(1,338)	(1,232)
Discontinued Operations for Segment Margin Reconciliation	0	(147)
Income from continuing operations before income taxes	$ 30,416	$ 22,500