Fair Values of Financial and Nonfinancial Instruments (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial and nonfinancial instruments
Gains (losses) realized on the IRLC pipeline	$ (988,000)	$ 480,000	$ 1,400,000
Gains (losses) from instruments used to hedge IRLCs	(12,600,000)	8,800,000	(8,100,000)
Gains on loan sales	32,300,000	17,000,000	26,600,000
Impairment charges	2,402,000	2,022,000	6,262,000
Measured on a non-recurring basis | Housing inventory
Financial and nonfinancial instruments
Impairment charges	0	0	1,900,000
Fair value of impaired assets			2,900,000
Measured on a non-recurring basis | Other assets held-for-sale
Financial and nonfinancial instruments
Impairment charges	0	154,000	41,000
Fair value of impaired assets		596,000	263,000
Measured on a non-recurring basis | Investments in joint ventures
Financial and nonfinancial instruments
Impairment charges	0	0	40,000
Fair value of impaired assets			$ 1,300,000