it all comes out in the wash

1. No permanent or lasting effects will occur as a result; things will normalize over time. I wouldn't worry too much about processing the invoice incorrectly; it all comes out in the wash. A: "Do you think Mark hates me after what I said at the party?" B: "Nah, it all comes out in the wash." Don't worry about paying me back for dinner. It all comes out in the wash eventually.

2. A lie or other secret will be uncovered eventually. The mayor is trying to cover something up, but it all comes out in the wash. You can only hide an affair for long. It all comes out in the wash sooner or later. We'll find out more soon enough. Whenever cases like this go to court, it all comes out in the wash.