Significant Accounting Policies (Share-Based Compensation Expense Schedule) (Details Textuals) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total amount charged to income	$ 14,383	$ 9,483	$ 7,556
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	3,235	2,102	1,670
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total amount charged to income	12,546	8,240	6,405
Operating Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total amount charged to income	1,837	1,243	1,151
Noncontrolling Interest [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total amount charged to income	$ 5,656	$ 3,813	$ 3,052