| **Segment Information (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
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| **Segment Reporting [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
| Information by Business Segment  | Information by business segment is as follows: 201620152014OPERATING REVENUE:     Residential real estate (a)$19,483 $21,137 $61,444Commercial real estate2,187 7,160 3,265Resorts and leisure 57,284 54,488 48,414Leasing operations9,742 8,978 6,977Forestry revenue (b)6,673 12,042 581,442Other375 66 331Consolidated operating revenue$95,744 $103,871 $701,873      COST OF REVENUE:     Cost of residential real estate revenue  (c)$6,383 $10,853 $27,562Cost of commercial real estate revenue1,323 4,974 1,031Cost of resorts and leisure revenue 50,229 47,069 42,900Cost of leasing revenue3,108 2,792 2,253Cost of forestry revenue  (d)1,121 1,402 63,029Cost of other revenue30 4 23Consolidated cost of revenue$62,194 $67,094 $136,798      OTHER OPERATING AND CORPORATE EXPENSES:     Residential real estate$5,744 $10,215 $8,269Commercial real estate2,167 2,104 2,271Resorts and leisure 547 426 452Leasing operations1,325 927 557Forestry revenue530 941 1,910Other12,706 18,813 12,669Consolidated other operating and corporate expenses$23,019 $33,426 $26,128      DEPRECIATION, DEPLETION AND AMORTIZATION:     Residential real estate$286 $544 $662Resorts and leisure4,402 5,096 4,143Leasing operations3,137 3,118 2,685Forestry552 581 729Other194 147 203Consolidated depreciation, depletion and amortization$8,571 $9,486 $8,422      INVESTMENT INCOME, NET     Residential real estate and other$97 $571 $994Corporate (e)17,679 22,117 11,697Consolidated investment income, net$17,776 $22,688 $12,691       201620152014INTEREST EXPENSE     Residential real estate$(1,284) $(1,174) $(1,316)Commercial and other (2,169) (1,489) (696)Corporate (f)(8,842) (8,766) (6,596)Consolidated interest expense$(12,295) $(11,429) $(8,608)      INCOME (LOSS) BEFORE EQUITY IN LOSS FROM UNCONSOLDIATED AFFILIATES AND INCOME TAXES:     Residential real estate (a) (c)$5,887 $(821) $24,854Commercial real estate(1,323) 126 (163)Resorts and leisure2,087 1,819 1,559Leasing operations90 676 1,165Forestry (b) (d)5,609 10,259 517,087Corporate (e)(f)(g)10,261 (13,222) (22,681)Consolidated income (loss) before equity in loss from unconsolidated affiliates and income taxes$22,611 $(1,163) $521,821         2016 2015 2014CAPITAL EXPENDITURES:     Residential real estate$3,319 $4,923 $4,981Commercial real estate3,937 2,165 854Resorts and leisure1,287 2,526 2,198Leasing operations2,899 5,849 22,600Forestry1,095 1,366 1,537Other321 636 271Total capital expenditures$12,858 $17,465 $32,441 December 31, 2016 December 31, 2015TOTAL ASSETS:   Residential real estate$112,220 $109,791Commercial real estate62,009 62,649Resorts and leisure73,436 75,441Leasing operations79,004 81,400Forestry20,664 20,244Other680,612 633,217Total assets$1,027,945 $982,742(a)Includes revenue of $43.6 million from the RiverTown Sale in 2014. (b)Includes revenue of $570.9 million from the AgReserves Sale in 2014.(c)Includes cost of revenue of $17.6 million from the RiverTown Sale in 2014.(d)Includes cost of revenue of $58.4 million from the AgReserves Sale in 2014.(e)Includes interest income from investments in SPEs of $8.2 million in both 2016 and 2015 and $6.1 million in 2014. (f)Includes interest expense from Senior Note issued by SPE of $8.8 million in both 2016 and 2015 and $6.6 million in 2014.(g)Includes pension charges of $13.5 million in 2014. |

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| - Definition
Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.
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