Segments - Schedule of Each Reportable Segment Information of Predecessor (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended							11 Months Ended	12 Months Ended
	Dec. 31, 2014	Nov. 23, 2014	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Nov. 23, 2014	Dec. 31, 2015	Dec. 31, 2013
Revenues
Rental income	$ 57,465										$ 586,530
Tenant reimbursement income	5,865										50,885
Fee and other income	2,805										24,993
Total revenues	66,135		$ 170,528	$ 167,726	$ 162,928	$ 161,226					662,408
Total expenses	62,699										591,789
Operating income (loss)	3,436										70,619
Income from unconsolidated joint ventures	938										6,850
Unrealized gain (loss) on interest rate swaps	15,084										75,760
Interest and other income (loss), net	(179)										871
Interest and debt expense	(43,743)										(168,366)
Net income before income taxes	73,227										23,709
Income tax expense	(505)										(2,566)
Net income	72,722										21,143
Net (loss) income attributable to common stockholders	57,308		8,905	$ 1,116	$ (4,709)	$ (9,731)					(4,419)
Total assets	9,030,441		8,794,143								8,794,143
Total liabilities	3,475,488		3,483,593								3,483,593
Total equity	5,554,953		5,310,550								5,310,550
Owned Properties [Member]
Revenues
Rental income	57,169										583,825
Tenant reimbursement income	5,865										50,885
Fee and other income	1,629										14,737
Total revenues	64,663										649,447
Total expenses	61,091										541,774
Operating income (loss)	3,572										107,673
Income from unconsolidated joint ventures	938										6,734
Unrealized gain (loss) on interest rate swaps	15,084										75,760
Interest and other income (loss), net	30										367
Interest and debt expense	(41,633)										(160,058)
Net income before income taxes	(22,009)										30,476
Income tax expense	(475)										310
Net income	(22,484)										30,786
Total assets	8,345,966		8,172,529								8,172,529
Total liabilities	3,350,798		3,309,104								3,309,104
Total equity	$ 4,995,168		$ 4,863,425								$ 4,863,425
Predecessor [Member]
Revenues
Rental income										$ 30,208		$ 30,406
Tenant reimbursement income										1,646		1,821
Distributions from real estate fund investments										17,083		29,184
Realized and unrealized gains, net										129,354		332,053
Fee and other income										49,098		26,426
Total revenues		$ 36,043					$ 71,392	$ 58,328	$ 61,626	227,389		419,890
Total expenses										76,992		88,299
Operating income (loss)										150,397		331,591
Income from unconsolidated joint ventures										4,241		1,062
Unrealized gain (loss) on interest rate swaps										(673)		1,615
Interest and other income (loss), net										2,479		9,407
Interest and debt expense										(28,585)		(29,807)
Net income before income taxes										127,859		313,868
Income tax expense										(18,461)		(11,029)
Net income										109,398		302,839
Net income attributable to noncontrolling interests										(87,888)		(286,325)
Net (loss) income attributable to common stockholders		$ (968)					$ 12,904	$ 5,178	$ 4,396	21,510		16,514
Total assets												2,922,691
Total liabilities												897,247
Total equity												2,025,444
Predecessor [Member] | Operating Segments [Member] | Owned Properties [Member]
Revenues
Rental income										27,774		30,406
Tenant reimbursement income										1,646		1,821
Total revenues										29,420		32,227
Total expenses										20,553		26,369
Operating income (loss)										8,867		5,858
Income from unconsolidated joint ventures										4,241		1,062
Interest and other income (loss), net										2,004		5,891
Interest and debt expense										(11,157)		(12,443)
Net income before income taxes										3,955		368
Net income										3,955		368
Net (loss) income attributable to common stockholders										3,955		368
Total assets												552,474
Total liabilities												350,884
Total equity												201,590
Predecessor [Member] | Operating Segments [Member] | Managed Funds [Member]
Revenues
Rental income										2,434
Distributions from real estate fund investments										17,083		29,184
Realized and unrealized gains, net										129,354		332,053
Total revenues										148,871		361,237
Total expenses										27,995		29,417
Operating income (loss)										120,876		331,820
Unrealized gain (loss) on interest rate swaps										(673)		1,615
Interest and other income (loss), net										388		1,152
Interest and debt expense										(17,323)		(17,219)
Net income before income taxes										103,268		317,368
Net income										103,268		317,368
Net income attributable to noncontrolling interests										(87,888)		(286,325)
Net (loss) income attributable to common stockholders										15,380		31,043
Total assets												2,329,153
Total liabilities												508,481
Total equity												1,820,672
Predecessor [Member] | Operating Segments [Member] | Management Company [Member]
Revenues
Fee and other income										74,686		54,298
Total revenues										74,686		54,298
Total expenses										54,032		60,385
Operating income (loss)										20,654		(6,087)
Income from unconsolidated joint ventures										48,683		74,695
Interest and other income (loss), net										87		2,364
Interest and debt expense										(105)		(145)
Net income before income taxes										69,319		70,827
Income tax expense										(18,461)		(11,029)
Net income										50,858		59,798
Net (loss) income attributable to common stockholders										50,858		59,798
Total assets												373,173
Total liabilities												96,596
Total equity												276,577
Predecessor [Member] | Eliminations [Member]
Revenues
Fee and other income										(25,588)		(27,872)
Total revenues										(25,588)		(27,872)
Total expenses										(25,588)		(27,872)
Income from unconsolidated joint ventures										(48,683)		(74,695)
Net income before income taxes										(48,683)		(74,695)
Net income										(48,683)		(74,695)
Net (loss) income attributable to common stockholders										$ (48,683)		(74,695)
Total assets												(332,109)
Total liabilities												(58,714)
Total equity												$ (273,395)