XML 82 R16.htm IDEA: XBRL DOCUMENT
v3.19.3

Interest Receivable | 12 Months Ended
--- | ---
Sep. 30, 2019
Receivables [Abstract] |
Interest Receivable | INTEREST RECEIVABLE The following table provides a summary of interest receivable by interest earning asset type.
| September 30, 2019 |  | September 30, 2018
| (In thousands)
Loans receivable | $ | 41,429 |  |  | $ | 39,176 |
Mortgage-backed securities | 6,107 |  |  | 6,404 |
Investment securities | 1,321 |  |  | 1,715 |
| $ | 48,857 |  |  | $ | 47,295 |

X
- References No definition available. + Details
Name: | us-gaap_ReceivablesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Interest Receivable [Text Block] + References No definition available. + Details
Name: | wfsl_InterestReceivableTextBlock
Namespace Prefix: | wfsl_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration