Investments in Unconsolidated Joint Ventures: Financial Results (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Assets:
Properties, net	$ 2,967,878	$ 3,435,737
Other assets	208,726	295,719
Total assets	3,176,604	3,731,456
Liabilities and partners' capital:
Mortgage notes payable	2,038,379	3,518,215
Other liabilities	195,766	202,444
Company's capital	489,349	(25,367)
Outside partners' capital	453,110	36,164
Total liabilities and partners' capital	3,176,604	3,731,456
Investment in unconsolidated joint ventures:
Company's capital	489,349	(25,367)
Basis adjustment	464,826	474,658
Investments in unconsolidated joint ventures	954,175	449,291
Assets—Investments in unconsolidated joint ventures	984,132	701,483
Liabilities—Distributions in excess of investments in unconsolidated joint ventures	(29,957)	(252,192)
Mortgage notes payable that could become recourse debt to the Company	33,540	35,540
Indemnity of guaranteed amount	16,770	16,770
Amortization of difference between cost of investments and book value of underlying equity	5,109	10,734	15,480
Revenues:
Minimum rents	388,363	418,724	512,002
Percentage rents	17,161	19,589	23,087
Tenant recoveries	186,741	204,171	250,168
Other	40,705	45,627	46,239
Total revenues	632,970	688,111	831,496
Expenses:
Shopping center and operating expenses	215,412	229,818	287,234
Interest expense	137,087	145,322	199,916
Depreciation and amortization	144,403	147,309	177,997
Total operating expenses	496,902	522,449	665,147
(Loss) gain on sale of assets	3,643	190,526	29,301
Gain on early extinguishment of debt		14
Net income	139,711	356,202	195,650
Company's equity in net income	60,626	167,580	79,281
Northwestern Mutual Life (NML)
Investment in unconsolidated joint ventures:
Mortgage notes payable to affiliate	606,263	712,455
Interest expense on borrowings from related party	38,113	31,549	43,732
Pacific Premier Retail LP
Assets:
Total assets	0	775,012
Investment in unconsolidated joint ventures:
Total liabilities	0	812,725
Revenues:
Minimum rents	88,831	118,164	132,247
Percentage rents	2,652	4,586	5,390
Tenant recoveries	40,118	52,470	56,397
Other	4,090	5,882	5,650
Total revenues	135,691	181,102	199,684
Expenses:
Shopping center and operating expenses	37,113	53,039	59,329
Interest expense	34,113	43,445	52,139
Depreciation and amortization	29,688	39,616	43,031
Total operating expenses	100,914	136,100	154,499
(Loss) gain on sale of assets	(7,044)	182,754	90
Gain on early extinguishment of debt		0
Net income	27,733	227,756	45,275
Company's equity in net income	9,743	110,798	23,026
Tysons Corner LLC
Assets:
Total assets	341,931	356,871
Investment in unconsolidated joint ventures:
Total liabilities	871,933	887,413
Revenues:
Minimum rents	64,521	62,072	63,569
Percentage rents	2,091	2,057	1,929
Tenant recoveries	47,084	45,452	44,225
Other	3,472	3,110	3,341
Total revenues	117,168	112,691	113,064
Expenses:
Shopping center and operating expenses	38,786	36,798	35,244
Interest expense	31,677	15,751	11,481
Depreciation and amortization	19,880	18,139	19,798
Total operating expenses	90,343	70,688	66,523
(Loss) gain on sale of assets	0	0	0
Gain on early extinguishment of debt		14
Net income	26,825	42,017	46,541
Company's equity in net income	7,080	15,126	17,969
Other Joint Ventures
Revenues:
Minimum rents	235,011	238,488	316,186
Percentage rents	12,418	12,946	15,768
Tenant recoveries	99,539	106,249	149,546
Other	33,143	36,635	37,248
Total revenues	380,111	394,318	518,748
Expenses:
Shopping center and operating expenses	139,513	139,981	192,661
Interest expense	71,297	86,126	136,296
Depreciation and amortization	94,835	89,554	115,168
Total operating expenses	305,645	315,661	444,125
(Loss) gain on sale of assets	10,687	7,772	29,211
Gain on early extinguishment of debt		0
Net income	85,153	86,429	103,834
Company's equity in net income	$ 43,803	$ 41,656	$ 38,286