Business Combinations (Pro Forma Impact Of Acquisitions) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Business Acquisition [Line Items]
Revenues, Pro Forma	$ 131,577	[1]	$ 122,698	[1]	$ 258,279	[1]	$ 241,636	[1]
Net income, Pro Forma	104,178	[1]	32,495	[1]	148,995	[1]	55,011	[1]
Net income attributable to common shareholders, Pro Forma	$ 45,421	[1]	$ 22,284	[1]	$ 79,089	[1]	$ 34,490	[1]
Earnings per share - basic, Pro Forma	$ 0.37	[1]	$ 0.18	[1]	$ 0.65	[1]	$ 0.29	[1]
Earnings per share - diluted, Pro Forma	$ 0.37	[1]	$ 0.18	[1]	$ 0.65	[1]	$ 0.29	[1]

[1] There are no non-recurring pro forma adjustments included within or excluded from the amounts in the preceding table.