Bank subsidiary (Details 18) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Maximum
Guarantees
Current standard deposit insurance amount	$ 250,000
Prior standard deposit insurance amount	100,000
Temporarily raised standard deposit insurance amount in prior period	250,000
American Savings Bank FSB and Subsidiaries [Member]
Guarantees
Spread added to current assessment rate (as a percent)	3.00%
Prepaid assessment	24,000,000	5,700,000
Assessment rate ( as a percent)		14.00%
FDIC insurance assessment	3,600,000
American Savings Bank FSB and Subsidiaries [Member] | Minimum
Guarantees
Assessment rate for financial institutions in the lowest risk category (as a percent)	2.50%
Assessment rate for financial institutions in the highest risk category (as a percent)	30.00%
American Savings Bank FSB and Subsidiaries [Member] | Maximum
Guarantees
Assessment rate for financial institutions in the lowest risk category (as a percent)	9.00%
Assessment rate for financial institutions in the highest risk category (as a percent)	45.00%
Indemnification Agreement | American Savings Bank FSB and Subsidiaries [Member]
Guarantees
Accrued indemnification litigation obligation	$ 1,100,000