Minimum percentage of average gross margin from home sales excluding impairments.

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The percentage by which "Performance Revenues" exceed the "Base Revenues".

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Share-Based Compensation Arrangement By Share Based Payment Award, Percentage Of Performance Revenues That Exceed Base Revenues, Period

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The percentage of target goal number of shares that will be earned upon achieving the conditions specified under the established share-based compensation plan.

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Amount of decrease to equity for grantee's tax withholding obligation for award under share-based payment arrangement.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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 of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Stock Based Compensation - Narrative (Details) - USD ($)	12 Months Ended			60 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jul. 14, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period, weighted average fair value (in dollars per share)	$ 14.66	$ 8.73	$ 7.30
Exercises in period, intrinsic value	$ 5,100,000	$ 40,200,000	$ 8,200,000
Average home sales revenues Performance Period	3 years
Grant date fair value (in dollars per share)	$ 53.47	$ 39.93	$ 31.34
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 3,000,000	$ 2,900,000	$ 1,500,000
Share-based payment arrangement, expense, tax benefit	100,000	0	0
Option, cost not yet recognized, amount	$ 2,200,000
Cost not yet recognized, period for recognition	1 year
Proceeds from stock options exercised	$ 2,600,000	37,900,000	25,300,000
Exercise of option, tax benefit	1,100,000	7,200,000	200,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	10,100,000	8,200,000	4,800,000
Share-based payment arrangement, expense, tax benefit	$ 1,400,000	1,200,000	700,000
Cost not yet recognized, period for recognition	1 year 4 months 24 days
Cost not yet recognized, amount, total	$ 6,900,000
Aggregate intrinsic value, nonvested	19,400,000
Aggregate intrinsic value, vested	$ 13,400,000	$ 8,600,000	$ 5,300,000
Restricted Stock \| Equity Incentive Plan 2011 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	5 years
Performance Shares \| Equity Incentive Plan 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average gross margin of home sales, percentage, minimum				15.00%
Shares withheld for tax withholding obligation	316,620	323,280	292,378
Decrease for tax withholding obligation	$ 18,800,000	$ 9,100,000	$ 10,000,000
Performance Shares \| Equity Incentive Plan 2011 \| Granted in 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense			1,800,000
Performance Shares \| Equity Incentive Plan 2011 \| Granted In 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense		1,400,000	11,700,000
Performance Shares \| Equity Incentive Plan 2011 \| Granted in 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	1,300,000	7,300,000	6,300,000
Performance Shares \| Equity Incentive Plan 2011 \| Granted in 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	7,300,000	$ 10,300,000	$ 0
Performance Shares \| Equity Incentive Plan 2011 \| Granted in 2020 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	13,400,000
Performance Shares \| Equity Incentive Plan 2011 \| Granted in 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense	$ 4,400,000
Performance Shares \| Equity Incentive Plan 2011 \| 5% to 10% Vesting Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target goal number of shares				50.00%
Performance Shares \| Equity Incentive Plan 2011 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				3 years
Percentage of performance revenues that exceed base revenues				10.00%
Performance Shares \| Equity Incentive Plan 2011 \| Minimum \| 5% to 10% Vesting Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance revenues that exceed base revenues				5.00%
Performance Shares \| Equity Incentive Plan 2011 \| Minimum \| 20% Vesting Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance revenues that exceed base revenues				20.00%
Performance Shares \| Equity Incentive Plan 2011 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance revenues that exceed base revenues				20.00%
Performance Shares \| Equity Incentive Plan 2011 \| Maximum \| 5% to 10% Vesting Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance revenues that exceed base revenues				10.00%
Performance Shares \| Equity Incentive Plan 2011 \| Maximum \| 20% Vesting Threshold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target goal number of shares				200.00%
Black-scholes Model
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period, weighted average fair value (in dollars per share)	$ 14.66	$ 8.73	$ 7.30