Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014 score	Dec. 31, 2013 score	Dec. 31, 2012 score	Dec. 31, 2011 score	Dec. 31, 2010 score	Dec. 31, 2009 score
Commitments and Contingencies
Mortgage loan types originated (as a percent)	100.00%	100.00%	100.00%	100.00%	100.00%	100.00%
Average FICO credit score	733	733	731	726	723	717
Average combined loan-to-value ratio (as a percent)	88.60%	89.80%	90.10%	90.30%	90.80%	91.40%
Mortgage interest rate lock commitments ("IRLCs")
Commitments and Contingencies
Maximum number of days of interest rate commitment before closing	180 days
Maximum number of days of loan commitment extension	270 days	270 days
Notional amount	$ 281.5	$ 269.2
Development bonds
Commitments and Contingencies
Guarantee obligations estimated exposure pertaining to land development and improvements	150.8	138.9
Performance-related cash deposits and letters of credit
Commitments and Contingencies
Guarantee obligations estimated exposure pertaining to land development and improvements	59.4	64.0
Prime
Commitments and Contingencies
Mortgage loan types originated (as a percent)	65.60%	57.20%	48.60%	42.20%	34.90%	32.90%
Government (FHA/VA/USDA)
Commitments and Contingencies
Mortgage loan types originated (as a percent)	34.40%	42.80%	51.40%	57.80%	65.10%	67.10%
Lot option purchase contracts
Commitments and Contingencies
Cash deposits and/or letters of credit	72.7	73.0
Aggregate purchase price	877.4	869.1
Purchase commitments, specific performance	$ 2.4	$ 2.5