I used to work at a bank as a teller.
Checks (of any amount)
do not get reported.
Cash transactions over $10,000 (in or out of your account) must be reported via a form that the bank fills out.
That said, any transaction that the bank deems "suspicious" can be reported without meeting the $10k threshold.
The bank that I used to work at was in a relatively affluent area, and I would see several personal deposits (via check) per day over 10k. If every one of these things were required to be reported, the IRS would have their hands full with the forms.
Here's the form if anyone is interested.