Investment Securities (Narrative) (Details) (USD $)	12 Months Ended
Dec. 31, 2014 securities	Dec. 31, 2013 securities	Dec. 31, 2012 securities
Investments, Debt and Equity Securities [Abstract]
Securities classified as trading	0us-gaap_TradingSecurities	0us-gaap_TradingSecurities
Discount interest rate (percent)	9.40%	6.40%
Average prepayment rate (percent)	6.00%	6.00%
Impairment recorded through other comprehensive income (loss)	0	0
Total carrying value of pledged securities	216,700,000hfwa_SecuritiesPledgedasCollateral	114,800,000hfwa_SecuritiesPledgedasCollateral
Private residential collateralized mortgage obligations
Investment Securities (Textual) [Abstract]
Mortgage backed securities evaluation non temporary decline number (securities)	4	8	8

Average prepayment rate used in the valuation of present value of impaired investment securities

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Discount interest rate used in the valuation of present value of impaired investment securities

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Number of securities, other than temporally impaired.

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Securities Pledged as Collateral

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Amount after tax of other than temporary impairment (OTTI) loss on investments in available-for-sale and held-to-maturity debt securities, recognized in other comprehensive loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 35

-Paragraph 35

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-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (g)

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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-Name Accounting Standards Codification

-Topic 320

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-Section 45

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-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.4)

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-Name Accounting Standards Codification

-Glossary Trading Securities

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