Income Taxes - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended
	Oct. 05, 2017	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Effective income tax rate, percent		1.00%	146.00%	1.00%	57.00%
Deferred Tax Assets, Net Of Deferred Tax Liabilities		$ 37,191,000		$ 37,191,000		$ 41,606,000
Statutory tax rate, percentage				21.00%	35.00%
Valuation allowance, deferred tax asset, amount		35,880,000		$ 35,880,000		$ 39,578,000
Unrecognized tax benefits		$ 441,000		$ 441,000
Majority Shareholder [Member] | D.R. Horton, Inc. [Member]
Sale of Stock, Percentage of Ownership after Transaction	75.00%