State tax filing

The standard deduction applies to your Federal tax return.  Here's a TurboTax video with more information about it. 

The payments that are being spread over three years from your Idaho tax return will stay within the Idaho state rules / standard deduction, etc.  and it will not change due to the fact that you moved to WA.  

 

Receiving a standard deduction every year does not wipe out your tax liability. It lowers your taxable income in the year that you file and can't be applied to a past tax arrear.