Fair value measurements (Details 2) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Fair value measurements on a recurring basis
Available-for-sale securities	$ 590,648,000us-gaap_AvailableForSaleSecurities	$ 550,394,000us-gaap_AvailableForSaleSecurities
Level 1 \| Forward sale contracts
Derivative liabilities
Derivative liabilities	0	0
Fair value measurements on a recurring basis \| Level 1
Derivative assets
Derivative assets	0	0
Derivative liabilities
Derivative liabilities	249,000	71,000
Fair value measurements on a recurring basis \| Level 1 \| Forward sale contracts
Derivative assets
Derivative assets	0	0
Derivative liabilities
Derivative liabilities	249,000	71,000
Fair value measurements on a recurring basis \| Level 2
Derivative assets
Derivative assets	851,000	398,000
Derivative liabilities
Derivative liabilities	32,000	43,000
Fair value measurements on a recurring basis \| Level 2 \| Interest rate lock commitments
Derivative assets
Derivative assets	836,000	393,000
Derivative liabilities
Derivative liabilities	1,000	3,000
Fair value measurements on a recurring basis \| Level 2 \| Forward sale contracts
Derivative assets
Derivative assets	15,000	5,000
Derivative liabilities
Derivative liabilities	31,000	40,000
Fair value measurements on a recurring basis \| Level 2 \| Bank
Fair value measurements on a recurring basis
Available-for-sale securities	590,648,000	550,394,000
Fair value measurements on a recurring basis \| Level 2 \| Other
Fair value measurements on a recurring basis
Money market funds	10,000	10,000
Fair value measurements on a recurring basis \| Level 2 \| Mortgage-related securities - FNMA, FHLMC and GNMA \| Bank
Fair value measurements on a recurring basis
Available-for-sale securities	450,421,000	430,834,000
Fair value measurements on a recurring basis \| Level 2 \| U.S. Treasury federal agency obligations \| Bank
Fair value measurements on a recurring basis
Available-for-sale securities	140,227,000	119,560,000
Fair value measurements on a nonrecurring basis \| American Savings Bank (ASB)
Derivative liabilities
Adjustments to fair value of loans held for sale	0	0
Fair value measurements on a nonrecurring basis \| Level 3
Derivative liabilities
Loans	2,494,000	2,445,000
Real estate acquired in settlement of loans	665,000	288,000
Estimated fair value
Fair value measurements on a recurring basis
Money market funds	10,000	10,000
Available-for-sale securities	590,648,000	550,394,000
Derivative assets
Derivative assets	851,000	398,000
Derivative liabilities
Derivative liabilities	281,000	114,000
Loans	4,616,814,000	4,578,822,000
Estimated fair value \| Level 1
Derivative assets
Derivative assets	0	0
Derivative liabilities
Derivative liabilities	249,000	71,000
Estimated fair value \| Level 2
Fair value measurements on a recurring basis
Money market funds	10,000	10,000
Available-for-sale securities	590,648,000	550,394,000
Derivative assets
Derivative assets	851,000	398,000
Derivative liabilities
Derivative liabilities	32,000	43,000
Estimated fair value \| Level 3
Derivative liabilities
Loans	4,616,814,000	4,578,822,000
Estimated fair value \| Fair value measurements on a nonrecurring basis
Derivative liabilities
Loans	2,494,000	2,445,000
Real estate acquired in settlement of loans	$ 665,000	$ 288,000

Represents the amount of fair value adjustments in loans held for sale.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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-Name Accounting Standards Codification

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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-Publisher FASB

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-Topic 310

-SubTopic 10

-Glossary Loan

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Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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-Name Regulation S-X (SX)

-Number 210

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-Article 12

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