Earnings (Loss) per share - Proforma Earnings (Loss) per share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Numerator
Net loss attributable to UCP, Inc.	$ (1,926)	$ (15)	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ (1,941)	$ 0	$ 0
Denominator
Pro forma net income (loss) per share - basic and diluted (in shares)									7,750,000
Common Class A [Member]
Denominator
Pro forma net income (loss) per share - basic and diluted (in shares)									7,750,000
Net income (loss) per share of Class A common stock - basic and diluted (in dollars per share)									$ (0.25)