Derivatives (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Purchase Contracts contract	Dec. 31, 2011 Purchase Contracts contract	Jun. 30, 2012 Purchase Contracts TBA agreements contract	Dec. 31, 2011 Purchase Contracts TBA agreements contract	Jun. 30, 2012 Purchase Contracts IRLCs contract	Dec. 31, 2011 Purchase Contracts IRLCs contract	Jun. 30, 2012 Sale Contracts contract	Dec. 31, 2011 Sale Contracts contract	Jun. 30, 2012 Sale Contracts TBA agreements contract	Dec. 31, 2011 Sale Contracts TBA agreements contract	Jun. 30, 2012 Sale Contracts Forward agreements contract	Dec. 31, 2011 Sale Contracts Forward agreements contract
Derivatives
Number of Contracts					796	709	4	1	792	708	26	28	25	17	1	11
Notional					$ 179,357,000	$ 127,816,000	$ 41,250,000	$ 589,000	$ 138,107,000	$ 127,227,000	$ 532,374,000	$ 491,900,000	$ 530,194,000	$ 371,000,000	$ 2,180,000	$ 120,900,000
Fair Value					1,837,000	1,696,000	100,000		1,737,000	1,696,000	(1,112,000)	(1,971,000)	(1,100,000)	(1,183,000)	(12,000)	(788,000)
Total gains/(losses) recorded within Principal transactions	$ (4,200,000)	$ (9,000,000)	$ (7,300,000)	$ (12,000,000)