Acquisitions - Summary of Acquired Shopping Centers (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Gross Purchase Price	$ 339,400,000
Raleigh, NC [Member] | North Carolina [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	December 2012
Gross Purchase Price	44,800,000
Face Value of Mortgage Debt Assumed
Charlotte, NC [Member] | North Carolina [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	December 2012
Gross Purchase Price	106,400,000
Face Value of Mortgage Debt Assumed
Independence, MO [Member] | Missouri [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	September 2012
Gross Purchase Price	57,800,000
Face Value of Mortgage Debt Assumed	33,600,000
St. Louis, MO [Member] | Missouri [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	September 2012
Gross Purchase Price	6,500,000
Face Value of Mortgage Debt Assumed	3,400,000
Tucson, AZ [Member] | Arizona [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	August 2012
Gross Purchase Price	125,400,000
Face Value of Mortgage Debt Assumed	24,400,000
Phoenix, AZ [Member] | Arizona [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	July 2012
Gross Purchase Price	137,300,000
Face Value of Mortgage Debt Assumed	105,400,000
Phoenix Two [Member] | Arizona [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	April 2012
Gross Purchase Price	59,900,000
Face Value of Mortgage Debt Assumed	47,200,000
Portland, OR [Member] | Oregon [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	April 2012
Gross Purchase Price	77,900,000
Face Value of Mortgage Debt Assumed	56,600,000
Chicago [Member] | Illinois [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	March 2012
Gross Purchase Price	47,400,000
Face Value of Mortgage Debt Assumed
Columbus, OH [Member] | Ohio [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	December 2011
Gross Purchase Price	79,600,000
Face Value of Mortgage Debt Assumed	45,200,000
Charlotte Two [Member] | North Carolina [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	September 2011
Gross Purchase Price	74,000,000
Face Value of Mortgage Debt Assumed	50,800,000
Charlotte Three [Member] | North Carolina [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	September 2011
Gross Purchase Price	11,000,000
Face Value of Mortgage Debt Assumed	6,600,000
Colorado Springs, CO [Member] | Colorado [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	September 2011
Gross Purchase Price	25,000,000
Face Value of Mortgage Debt Assumed	9,600,000
Macedonia and Maple Grove [Member] | Ohio and Minnesota [Member]
Business Acquisition Gross Purchase Price And Mortgage Debt Assumed [Line Items]
Acquisition date of shopping centers	January and March 2011
Gross Purchase Price	79,700,000
Face Value of Mortgage Debt Assumed	$ 50,200,000