Long-term Debt - Propco Credit Agreement (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 14, 2013	Jun. 18, 2011	Jan. 03, 2012
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchase Price, Cash Tender Offer		0.9915
Debt Instrument, Repurchase Price, Consent Payment		0.01
Propco [Member] | Tranche B-1 [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount			$ 200,000,000
Propco [Member] | Tranche B-3 [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount			625,000,000	625,000,000
Propco [Member] | Tranche B-2 [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount			750,000,000
Propco [Member] | Credit Agreement [Member]
Debt Instrument [Line Items]
Number of additional extension periods for debt instrument			2
Debt instrument, term of extension period	1 year
Propco [Member] | Term Loan Facility [Member]
Debt Instrument [Line Items]
Number of debt tranches			3
Long-term debt, aggregate principal amount			1,575,000,000
Propco [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			125,000,000
Propco [Member] | Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt, aggregate principal amount				$ 625,000,000