I wasn't sure where to put this. I just randomly gained a million gil when I used a teleport!

https://imgur.com/a/TuOleCY

Is this just something that happens sometimes? I'm not complaining or anything; I'm just a little confused. And I'm hesitant to do anything with that money until I know it's not some weird glitch that will be suddenly reverted and leave me with negative wealth or something.