Summary of Significant Accounting Policies Summary of Significant Accounting Policies - Development Costs (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2013
Development Costs [Line Items]
Project Development Expenses	$ 16.0
Project development costs incurred		17.9
Architectural Fees [Member]
Development Costs [Line Items]
Project development costs incurred		10.4
Shared Development Expenses [Member]
Development Costs [Line Items]
Project development costs incurred		1.9
Legal Expense [Member]
Development Costs [Line Items]
Project development costs incurred		2.3
Construction Manager Costs [Member]
Development Costs [Line Items]
Project development costs incurred		1.0
Professional Services [Member]
Development Costs [Line Items]
Project development costs incurred		0.9
Agreement Payments [Member]
Development Costs [Line Items]
Project development costs incurred		$ 1.5