Business Segments Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenue	$ 567,842	$ 476,423	$ 1,563,797	$ 1,340,269
Operating Income	43,862	39,277	113,508	99,842
Interest	4,426	4,675	15,192	13,847
Equity in income from joint venture arrangements	(44)	(71)	(268)	(198)
Acquisition and integration costs	0	0	1,700	0
Income before income taxes	39,480	34,673	96,884	86,193
Purchase Accounting Adjustments	692		4,549
Standard Product Warranty Accrual, Period Increase (Decrease)	0	0	0	8,500
Midwest Homebuilding [Member]
Segment Reporting Information [Line Items]
Revenue	236,803	180,488	622,325	495,379
Operating Income	24,179	20,887	55,377	53,730
Interest	1,297	1,319	5,175	3,559
Southern Homebuilding [Member]
Segment Reporting Information [Line Items]
Revenue	221,044	176,502	649,014	504,647
Operating Income	18,922	13,082	53,142	26,503
Interest	1,679	2,143	5,874	6,311
Mid-Atlantic Homebuilding [Member]
Segment Reporting Information [Line Items]
Revenue	97,802	107,670	253,363	302,305
Operating Income	8,211	9,969	15,909	26,810
Interest	615	557	1,844	1,988
Financial Services [Member]
Segment Reporting Information [Line Items]
Revenue	12,193	11,763	39,095	37,938
Operating Income	5,681	5,887	21,159	21,977
Interest	835	656	2,299	1,989
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Selling, general and administrative expenses	$ (13,131)	$ (10,548)	$ (32,079)	$ (29,178)

Purchase Accounting Adjustments related to an acquisition

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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The net result for the period of deducting operating expenses from operating revenues.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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- Definition

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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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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- Definition

Amount of increase (decrease) in the standard product warranty accrual. Excludes extended product warranties.

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