Fair Value Measurements - Textual (Details)	3 Months Ended
Mar. 31, 2019 USD ($)
Fair Value Disclosures [Abstract]
Fair value assets transfers between level 1 and level 2 transfer amount	$ 0

Fair value assets transfers between level 1 and level 2 transfers amount.

No definition available.

Name:	hfwa_FairValueAssetsTransfersBetweenLevel1andLevel2TransfersAmount
Namespace Prefix:	hfwa_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration