Real Estate - Real Estate (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	$ 652,920	$ 607,133
Less: accumulated depreciation	(32,107)	(31,377)
Total Real Estate	620,813	575,756
Radisson Hotel [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	62,693	59,773
Less: accumulated depreciation	(28,396)	(29,062)
Net carrying value	34,297	30,711
Undeveloped land (includes land in entitlement) [Member] [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	93,824	93,182
Less: accumulated depreciation	0	0
Net carrying value	93,824	93,182
Entitled, developed and under development projects [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	359,532	321,273
Less: accumulated depreciation	0	0
Net carrying value	359,532	321,273
West Austin [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	9,075	8,866
Less: accumulated depreciation	0	0
Net carrying value	9,075	8,866
Downtown Edge [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	12,335	11,856
Less: accumulated depreciation	0	0
Net carrying value	12,335	11,856
Music Row [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	8,483	7,675
Less: accumulated depreciation	0	0
Net carrying value	8,483	7,675
Dillon [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	18,120	15,203
Less: accumulated depreciation	0	0
Net carrying value	18,120	15,203
Midtown [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	34,952	33,293
Less: accumulated depreciation	(1,399)	(231)
Net carrying value	33,553	33,062
Eleven [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	53,906	53,958
Less: accumulated depreciation	(2,312)	(576)
Net carrying value	51,594	53,382
Harbor Lakes [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Carrying value	0	2,054
Less: accumulated depreciation	0	(1,508)
Net carrying value	$ 0	$ 546