Nature of Operations and Significant Accounting Policies (Details) Property and Equipment (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 128,654	$ 108,842
Depreciation	4,300	565	439
Land, Buildings and Improvements
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment, minimum	15
Furniture and Fixtures
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment	7
Computer Equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment	3
Northstar | Plant Assets
Property, Plant and Equipment [Line Items]
Estimated useful lives of property and equipment, minimum	5
Estimated useful lives of property and equipment, maximum	30
Property and equipment, net	124,200
Depreciation	$ 3,500