Business Segment Information (Reconciliation Of Segment Margin To (Loss) Income from Continuing Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting [Abstract]
Segment margin	$ 82,681	$ 70,442	$ 160,032	$ 142,507
Corporate general and administrative expenses	(13,789)	(10,305)	(24,850)	(21,142)
Depreciation and amortization	(20,491)	(15,665)	(39,771)	(30,714)
Interest Income (Expense), Net	(14,069)	(12,255)	(26,873)	(23,696)
Distributable cash from equity investees in excess of equity in earnings	(7,808)	(4,891)	(13,585)	(11,455)
Non-cash items not included in segment margin	(3,043)	960	282	(3,335)
Cash payments from direct financing leases in excess of earnings	(1,371)	(1,263)	(2,709)	(2,495)
Income tax benefit (expense)	(962)	(117)	(1,603)	86
Discontinued Operations for Segment Margin Reconciliation	0	(294)	0	(441)
Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest	21,148	26,612	50,923	49,315
Income from continuing operations before income taxes	$ 22,110	$ 26,729	$ 52,526	$ 49,229