Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Nominal or face amount used to calculate payment on derivative.

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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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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Fair Value - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value measurement gain/(loss)	$ 15,583	$ 14,111
Senior Notes due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior Notes	598,925	598,301
Level 2 \| Fair Value, Measurements, Recurring \| Senior Notes due 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior Notes fair value	630,000	626,520
Home Building
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Senior Notes	1,517,395	598,301
Mortgage Banking
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance	449,760	492,125
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance	449,760	492,125
Mortgage Banking \| Level 2 \| Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value adjustment income (expense)	1,472	(198)	$ 8,485
Mortgage Banking \| Level 2 \| Fair Value, Measurements, Recurring \| Rate lock commitments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value measurement gain/(loss)	10,757
Derivative, Notional Amount	617,308
Derivative, Notional Amount	617,308
Mortgage Banking \| Level 2 \| Fair Value, Measurements, Recurring \| Forward sales contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value measurement gain/(loss)	(5,216)
Derivative, Notional Amount	916,588
Derivative, Notional Amount	916,588
Mortgage Banking \| Level 2 \| Fair Value, Measurements, Recurring \| Mortgages held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total fair value measurement gain/(loss)	10,042	7,019
Derivative, Notional Amount	439,718	485,106
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance	449,760	492,125
Financing Receivable, Held-for-Sale, Not Part of Disposal Group, after Valuation Allowance	449,760	492,125
Derivative, Notional Amount	$ 439,718	$ 485,106