Notes Payable (Details Textual) (USD $)	3 Months Ended				1 Months Ended				1 Months Ended					3 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Dec. 31, 2011	Dec. 31, 2012 Letter of Credit One [Member]	Jul. 25, 2012 Homebuilding [Member]	Dec. 31, 2012 Homebuilding [Member]	Sep. 30, 2012 Homebuilding [Member]	Nov. 01, 2012 Homebuilding [Member] Financing [Member]	Sep. 30, 2012 Homebuilding [Member] Line of Credit [Member]	Dec. 31, 2012 Homebuilding [Member] 2% convertible senior notes [Member]	Sep. 30, 2012 Homebuilding [Member] 2% convertible senior notes [Member]	Dec. 31, 2012 Financial Services [Member]	Sep. 30, 2012 Financial Services [Member]	Dec. 31, 2012 Financial Services [Member] Minimum [Member]	Dec. 31, 2012 Financial Services [Member] Maximum [Member]	Dec. 31, 2012 Dividend Declared [Member]	Dec. 31, 2012 Accelerated Dividend [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Term									5 years
Notes Payable [Abstract]
Base capacity of mortgage repurchase facility								$ 600,000,000	$ 125,000,000			$ 180,000,000
Line of credit facility additional borrowing capacity									375,000,000
Maximum capacity of mortgage repurchase facility								1,000,000,000				225,000,000
Letter of Credit, Maximum Borrowing Capacity								300,000,000
Line of Credit Facility, Interest Rate at Period End	4.80%
Line of Credit Facility, Amount Outstanding						100,000,000	0
Letters of Credit Outstanding, Amount	51,400,000			5,500,000
Cash dividends declared per common share (in dollars per share)	$ 0.1875		$ 0.0375													$ 0.0375	$ 0.15
Debt Conversion, Converted Instrument, Shares Issued	77.18004	76.5697
Principal amount	1,000
Debt Instrument, Convertible, Conversion Price										$ 12.96	$ 13.06
Incremental Common Shares Attributable to Conversion of Debt Securities	38,600,000		0
Authorized repurchase of debt securities					500,000,000
Debt repurchase program, remaining authorized repurchase amount						500,000,000
Repurchase of purchased loans specified time frame														45 days	120 days
Mortgage loans held for sale pledged under repurchase agreement												248,600,000
Mortgage loans, collateral value												235,300,000
Advance pay downs on mortgage repurchase facility												65,900,000
Mortgage repurchase facility												$ 169,400,000	$ 187,800,000
Interest rate on mortgage repurchase facility												2.80%