Deep Pockets
Having a lot of money.

The idiom implies that people or businesses with deep (large) pockets are able to carry a lot of money. They probably don't actually keep it all in their pockets, though.

"They can afford this house because they have deep pockets."

"The company didn't do well this year, but it has deep pockets so it'll be fine."

*Sometimes the expression "Short arms and deep pockets" will be used to describe someone with a lot of money, though rarely uses it - he or she can't reach into his or her pockets.