Business Segments Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue	$ 653,345	$ 567,842	$ 1,758,140	$ 1,563,797
Operating Income	54,649	43,862	131,254	113,508
Interest	4,637	4,426	16,626	15,192
Equity in loss (income) from joint venture arrangements	(52)	(44)	(118)	(268)
Acquisition and integration costs	0	0	0	1,700
Income before income taxes	50,064	39,480	114,746	96,884
Northern Homebuilding [Member]
Segment Reporting Information [Line Items]
Revenue	270,063	236,803	723,295	622,325
Operating Income	29,587	24,179	70,559	55,377
Interest	1,505	1,297	5,360	5,175
Purchase Accounting Adjustments	100	700	600	4,500
Southern Homebuilding [Member]
Segment Reporting Information [Line Items]
Revenue	369,828	318,846	995,305	902,377
Operating Income	32,500	27,133	76,308	69,051
Interest	2,146	2,294	8,602	7,718
Financial Services Sector [Member]
Segment Reporting Information [Line Items]
Revenue	13,454	12,193	39,540	39,095
Operating Income	6,609	5,681	19,943	21,159
Interest	986	835	2,664	2,299
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Selling, general and administrative expenses	$ (14,047)	$ (13,131)	$ (35,556)	$ (32,079)

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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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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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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