Segment Information (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013
Financial data of five reportable segments
Total Assets	$ 8,208,930,000		$ 8,208,930,000		$ 8,952,025,000
Revenues	234,743,000	276,693,000	713,917,000	824,574,000
Operating Expenses	150,154,000	181,502,000	467,064,000	552,775,000
Depreciation and amortization	55,511,000	88,232,000	169,838,000	236,488,000
Interest expense	59,312,000	82,253,000	178,917,000	246,832,000
Interest and other income	10,096,000	14,957,000	33,974,000	37,382,000
Capital expenditures	83,360,000	104,877,000	315,170,000	345,395,000
Commercial Group [Member]
Financial data of five reportable segments
Total Assets	4,099,605,000		4,099,605,000		5,120,360,000
Revenues	129,345,000	160,965,000	383,221,000	511,767,000
Operating Expenses	70,224,000	85,986,000	224,929,000	283,313,000
Depreciation and amortization	29,304,000	62,961,000	91,756,000	162,748,000
Interest expense	31,093,000	49,465,000	97,938,000	148,893,000
Interest and other income	1,579,000	4,989,000	5,585,000	9,059,000
Capital expenditures	17,655,000	35,051,000	98,033,000	143,675,000
Residential Group [Member]
Financial data of five reportable segments
Total Assets	2,789,605,000		2,789,605,000		2,468,708,000
Revenues	63,303,000	69,423,000	190,525,000	196,704,000
Operating Expenses	43,704,000	50,081,000	127,046,000	145,105,000
Depreciation and amortization	16,608,000	15,748,000	49,660,000	45,769,000
Interest expense	8,030,000	8,241,000	23,032,000	24,957,000
Interest and other income	5,101,000	6,110,000	18,145,000	18,371,000
Capital expenditures	62,795,000	58,074,000	207,644,000	155,774,000
Arena [Member]
Financial data of five reportable segments
Total Assets	969,020,000		969,020,000		984,937,000
Revenues	25,039,000	25,277,000	84,968,000	76,270,000
Operating Expenses	17,105,000	16,286,000	55,399,000	56,596,000
Depreciation and amortization	8,793,000	8,699,000	25,999,000	25,073,000
Interest expense	10,895,000	9,492,000	30,101,000	27,767,000
Interest and other income	0	0	0	0
Capital expenditures	2,890,000	11,752,000	9,442,000	44,665,000
Land Development Group [Member]
Financial data of five reportable segments
Total Assets	267,392,000		267,392,000		260,070,000
Revenues	17,056,000	21,028,000	55,203,000	39,833,000
Operating Expenses	5,358,000	15,155,000	24,307,000	29,230,000
Depreciation and amortization	88,000	99,000	269,000	528,000
Interest expense	(287,000)	97,000	(572,000)	(341,000)
Interest and other income	3,384,000	3,793,000	10,091,000	9,725,000
Capital expenditures	20,000	0	36,000	829,000
Corporate Activities [Member]
Financial data of five reportable segments
Total Assets	83,308,000		83,308,000		117,950,000
Revenues	0	0	0	0
Operating Expenses	13,763,000	13,994,000	35,383,000	38,531,000
Depreciation and amortization	718,000	725,000	2,154,000	2,370,000
Interest expense	9,581,000	14,958,000	28,418,000	45,556,000
Interest and other income	32,000	65,000	153,000	227,000
Capital expenditures	$ 0	$ 0	$ 15,000	$ 452,000