Ask HN: Where do you store important information for your next of kin?

I manage most of my family's finances, insurance, bills, etc. There's nothing wild, but there are a lot of different accounts in different places. I would like to keep all of this information somewhere that would be easily accessible to my wife if I get hit by a bus, but that is secure enough that I don't have to worry about someone else making off with our life savings. What solutions have you all used for this sort of thing?