Acquisitions: Percentage Ownership (Details)	Nov. 14, 2014	Jun. 04, 2014	Oct. 24, 2013	Sep. 17, 2013
Cascade Mall
Acquisition
Ownership percentage at completion of acquisition (as a percent)		100.00%
Superstition Springs Land I
Acquisition
Ownership percentage at completion of acquisition (as a percent)			100.00%
Fair value of existing ownership interest (as a percent)			66.70%
Camelback Colonnade
Acquisition
Ownership percentage at completion of acquisition (as a percent)				100.00%
Fair value of existing ownership interest (as a percent)				73.20%
PPR Queens Portfolio
Acquisition
Ownership percentage at completion of acquisition (as a percent)	100.00%
Fair value of existing ownership interest (as a percent)	51.00%