Fair Value Measurements - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Fair Value Measurements Of Financial Instruments [Line Items]
Primary unobservable inputs used in discounted cash flow model			The two primary unobservable inputs used in our discounted cash flow model are the forecasted number of homes to be closed, as they drive any increases to the tax base for the Metropolitan District, and the discount rate.
Unrealized gain related to available-for-sale securities			$ 8,900,000		$ 4,800,000
Inventory impairments	0	0	0	0
Short-term maturities			30 days
Level 2 [Member]
Fair Value Measurements Of Financial Instruments [Line Items]
Mortgage loans held-for-sale	92,463,000		92,463,000		119,953,000
Under Commitment To Sell [Member] | Level 2 [Member]
Fair Value Measurements Of Financial Instruments [Line Items]
Mortgage loans held-for-sale	69,700,000		69,700,000		108,300,000
Not Under Commitment To Sell [Member] | Level 2 [Member]
Fair Value Measurements Of Financial Instruments [Line Items]
Mortgage loans held-for-sale	22,700,000		22,700,000		11,800,000
AFS Investments [Member]
Fair Value Measurements Of Financial Instruments [Line Items]
Marketable Securities, Unrealized Gain (Loss), net	$ 1,500,000				$ 4,800,000
Metropolitan district bond securities [Member]
Fair Value Measurements Of Financial Instruments [Line Items]
Maturity date			2037