Segment Information - Segment Revenues and Earnings (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Segment Reporting Information [Line Items]
Total revenues	$ 47,992	$ 43,625	$ 85,610	$ 80,999
Segment reporting information income (loss) from continuing operations before income taxes attributable to parent	26,591	3,382	32,583	(4,822)
General and administrative expense	(4,852)	(4,901)	(11,331)	(13,043)
Interest expense	(6,918)	(8,715)	(14,557)	(17,536)
Loss on extinguishment of debt, net	(35,766)	0	(35,864)	0
Other corporate non-operating income	199	783	371	1,700
Segment Earnings
Segment Reporting Information [Line Items]
Total revenues	47,992	43,625	85,610	80,999
Segment reporting information income (loss) from continuing operations before income taxes attributable to parent	74,026	17,250	94,222	27,297
Segment Earnings \| Real estate
Segment Reporting Information [Line Items]
Total revenues	46,381	39,409	82,479	72,239
Segment reporting information income (loss) from continuing operations before income taxes attributable to parent	73,290	15,527	93,514	24,593
Segment Earnings \| Mineral resources
Segment Reporting Information [Line Items]
Total revenues	1,337	2,360	2,419	5,114
Segment reporting information income (loss) from continuing operations before income taxes attributable to parent	933	1,766	1,486	3,138
Segment Earnings \| Other
Segment Reporting Information [Line Items]
Total revenues	274	1,856	712	3,646
Segment reporting information income (loss) from continuing operations before income taxes attributable to parent	(197)	(43)	(778)	(434)
Segment Reconciling Items
Segment Reporting Information [Line Items]
Segment reporting information income (loss) from continuing operations before income taxes attributable to parent	(47,435)	(13,868)	(61,639)	(32,119)
General and administrative expense	(4,514)	(5,177)	(9,487)	(11,197)
Shared-based and long-term incentive compensation expense	(412)	(23)	(1,956)	(3,481)
Interest expense	(6,918)	(8,715)	(14,557)	(17,536)
Loss on extinguishment of debt, net	(35,766)	0	(35,864)	0
Other corporate non-operating income	$ 175	$ 47	$ 225	$ 95

Income (Loss) from Continuing Operations before Income Taxes Attributable to Parent

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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-Publisher FASB
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount of the cost of borrowed funds accounted for as interest expense.

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- Definition

The aggregate amount of other income amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) profits on securities (net of losses), and (d) miscellaneous other income items.

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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