Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest expense	$ (24,185)	$ (21,707)	$ (23,559)
Income before taxes	846,911	661,697	603,212
Income tax expense	(309,390)	(236,435)	(220,285)
Net income	$ 537,521	$ 425,262	$ 382,927
Basic earnings per share (USD per share)	$ 144.00	$ 110.53	$ 95.21
Diluted earnings per share (USD per share)	$ 126.77	$ 103.61	$ 89.99
Basic weighted average shares outstanding (in Shares)	3,733	3,847	4,022
Diluted weighted average shares outstanding (in Shares)	4,240	4,104	4,255
Homebuilding:
Revenues	$ 6,175,521	$ 5,709,223	$ 5,065,200
Other income	6,536	2,820	2,956
Cost of sales	(4,990,378)	(4,707,861)	(4,118,782)
Selling, general and administrative	(392,272)	(382,459)	(371,127)
Operating income	799,407	621,723	578,247
Interest expense	(23,037)	(20,621)	(22,918)
Income before taxes	776,370	601,102	555,329
Mortgage Banking:
Mortgage banking fees	130,319	113,321	93,808
Interest income	7,850	7,569	6,485
Other income	2,048	1,652	1,113
General and administrative	(68,528)	(60,861)	(52,882)
Interest expense	(1,148)	(1,086)	(641)
Income before taxes	$ 70,541	$ 60,595	$ 47,883