Nature of Operations and Summary of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, shares in Thousands, $ in Thousands			12 Months Ended
	Jun. 14, 2018 USD ($)	Aug. 04, 2017 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) segment	Dec. 31, 2017 USD ($)	Jan. 01, 2019 USD ($)
Summary of Significant Accounting Policies [Line Items]
Number of operating segments | segment			5
Business combination net of acquired cash			$ 28,036	$ 130,047
Allowance for doubtful accounts receivable			0	0
Earnest money deposits			14,000	14,100
Impairment of real estate inventory			800	800
Forfeited deposits			1,500
Other income, land sales to third parties			7,700
Cost of land dispositions			7,800
Deferred revenue, related to unsatisfied performance obligations			2,300
Deferred costs, related to unsatisfied performance obligations			1,700
Non-refundable cash deposits			42,600	18,900
Reclassification of costs from inventory to property and equipment			2,300
Decrease retained earnings			600
Earnest money deposits			13,990	14,077
Mortgage loans held for sale			114,074	52,327
Tax valuation allowance			0	0
Reserves for uncetain tax positions			0	0
Goodwill impairment			0	0
Inspire [Member]
Summary of Significant Accounting Policies [Line Items]
Mortgage loans in process			26,200	10,000
Mortgage loans held for sale			114,100	52,300
Mortgage loans held for sale aggregate outstanding principal balance			$ 108,000	$ 50,400
UCP, Inc [Member]
Summary of Significant Accounting Policies [Line Items]
Conversion of stock, ratio		0.2309%
Business combination net of acquired cash		$ 100,150
Wade Jurney Homes [Member]
Summary of Significant Accounting Policies [Line Items]
Ownership interest	50.00%
Business combination, purchase price	$ 37,500
Minimum [Member]
Summary of Significant Accounting Policies [Line Items]
Estimated life of the community based			2 years
Minimum [Member] | Subsequent Event [Member]
Summary of Significant Accounting Policies [Line Items]
Operating Lease, Right-of-Use Asset					$ 16,000
Operating Lease, Liability					16,000
Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Estimated life of the community based			3 years
Maximum [Member] | Subsequent Event [Member]
Summary of Significant Accounting Policies [Line Items]
Operating Lease, Right-of-Use Asset					19,000
Operating Lease, Liability					$ 19,000
Common Class A [Member] | UCP, Inc [Member]
Summary of Significant Accounting Policies [Line Items]
Conversion of stock, cash | $ / shares		$ 5.32
Century Common Stock [Member] | UCP, Inc [Member]
Summary of Significant Accounting Policies [Line Items]
Conversion of stock, ratio		0.2309%
Shares issued in connection to merger | shares		4,176