Information by Business Segment (Parenthetical) (Detail) (USD $)	3 Months Ended				12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting Information [Line Items]
Impairment losses	$ 2,551,000	$ 374,846,000	$ 1,697,000	$ 782,000	$ 2,551,000	$ 377,325,000	$ 4,799,000
Pension charges					2,063,000	5,871,000	4,138,000
Resorts, leisure and leasing operations
Segment Reporting Information [Line Items]
Impairment losses					2,600,000	1,400,000
Investment in equity method investees	2,200,000	2,300,000			2,200,000	2,300,000
Residential Real Estate
Segment Reporting Information [Line Items]
Impairment losses						337,600,000	4,800,000
Commercial Real Estate
Segment Reporting Information [Line Items]
Impairment losses						38,200,000
Rural land
Segment Reporting Information [Line Items]
Impairment losses						100,000
Other
Segment Reporting Information [Line Items]
Pension charges					$ 2,100,000	$ 5,900,000	$ 4,100,000