Bank subsidiary (Details 2) (USD $)	Jun. 30, 2011	Dec. 31, 2010	Jun. 30, 2010	Dec. 31, 2009
Assets
Available-for-sale investment and mortgage-related securities	$ 711,347,000	$ 678,152,000
Investment in stock of Federal Home Loan Bank of Seattle	97,764,000	97,764,000
Loans receivable held for investment, net	3,580,418,000	3,489,880,000
Loans held for sale, at lower of cost or fair value	4,784,000	7,849,000
Other	494,527,000	487,614,000
Goodwill	82,190,000	82,190,000
Total assets	9,241,071,000	9,085,344,000
Liabilities and shareholders' equity
Other	796,573,000	823,479,000
Total liabilities	7,694,571,000	7,567,414,000
Common stock	1,343,537,000	1,314,199,000
Retained earnings	178,513,000	181,910,000
Accumulated other comprehensive loss, net of tax benefits	(9,843,000)	(12,472,000)
Total shareholders' equity	1,512,207,000	1,483,637,000	1,466,633,000	1,441,648,000
Total liabilities and shareholders' equity	9,241,071,000	9,085,344,000
Other assets
Premises and equipment, net	3,204,996,000	3,165,918,000
Total other assets	494,527,000	487,614,000
Other liabilities
Total other liabilities	796,573,000	823,479,000
American Savings Bank (ASB)
Assets
Cash and cash equivalents	178,251,000	204,397,000
Federal funds sold	1,249,000	1,721,000
Available-for-sale investment and mortgage-related securities	711,347,000	678,152,000
Investment in stock of Federal Home Loan Bank of Seattle	97,764,000	97,764,000
Loans receivable held for investment, net	3,580,418,000	3,489,880,000
Loans held for sale, at lower of cost or fair value	4,784,000	7,849,000
Other	234,524,000	234,806,000
Goodwill	82,190,000	82,190,000
Total assets	4,890,527,000	4,796,759,000
Liabilities and shareholders' equity
Deposit liabilities-noninterest-bearing	912,034,000	865,642,000
Deposit liabilities-interest-bearing	3,142,915,000	3,109,730,000
Other borrowings	239,122,000	237,319,000
Other	99,260,000	90,683,000
Total liabilities	4,393,331,000	4,303,374,000
Common stock	331,348,000	330,562,000
Retained earnings	170,157,000	169,111,000
Accumulated other comprehensive loss, net of tax benefits	(4,309,000)	(6,288,000)
Total shareholders' equity	497,196,000	493,385,000
Total liabilities and shareholders' equity	4,890,527,000	4,796,759,000
Other assets
Bank-owned life insurance	119,671,000	117,565,000
Premises and equipment, net	56,415,000	56,495,000
Prepaid expenses	17,700,000	18,608,000
Accrued interest receivable	15,178,000	14,887,000
Mortgage-servicing rights	6,854,000	6,699,000
Real estate acquired in settlement of loans, net	4,722,000	4,292,000
Other	13,984,000	16,260,000
Total other assets	234,524,000	234,806,000
Other liabilities
Accrued expenses	13,036,000	16,426,000
Federal and state income taxes payable	34,167,000	28,372,000
Cashier's checks	26,486,000	22,396,000
Advance payments by borrowers	10,061,000	10,216,000
Other	15,510,000	13,273,000
Total other liabilities	99,260,000	90,683,000
Balance Sheet related disclosures
Securities sold under agreements to repurchase	174,000,000	172,000,000
Advances from Federal Home Loan Bank	65,000,000	65,000,000
Loan commitments and unused lines and letters of credit	$ 1,300,000,000