Does Medicaid cover the entire expense for nursing home care?

In my state (WI), Medicaid covers nursing home stays. I did notice however, that some other nursing homes are starting to not accept medicaid because of the slow reimbursement from the state and piles of paperwork that the employees have to fill out.

Yes. My MIL (in MN) has only SS and Medicaid takes all but $90 every month. It also covers her phone and cable. She gets all the same care as the private pay residents, including medical care and medications, field trips, visits from the podiatrist and dental care. It will not fund her Resident Trust (for "extras" like manicures and hair styling) but that's what we do with the leftover $90 per month. Those trusts usually have a limit of about $250 total. It won't pay for clothing (but the NH will usually come up with "hand me downs" for people to use). If you fully fund the trust and don't use whatever is leftover and "extra" funds build up in her account, you can look into putting that towards a pre-paid funeral trust because Medicaid will allow that "asset". Otherwise the county will just take it. This is in the state of MN, so check with your county to make sure this holds true in your mom's location. Blessings.

My mom has to give the NH all of her income (SS and an annuity) less $62 per. month. Medicaid pays the rest.

Where I live rehab and LTC is in the same building. If Mom started out in rehab Medicare paid 100% for the first 20 days,50% for 21 to 100 days. Mom may have owed $160 a day. If she didn't have it, did u apply for Medicaid?

I don't know how it works if its just a long stay with the person returning home but if a "rest of ur life" thing, any monthly income Mom gets goes towards her care. That means her SS and any pension she has. All assets, but a house and car, have to be liquidated for her care. She can have, depending on your state, a small amount in the bank. She is allowed a small amt of her SS check (my state $50) for personal needs.

So, if Mom is there for the rest of her life, and owns a home, none of her income can be used for its upkeep.

No, not if your mother has any income. If your mother has social security or a pension, Medicaid should not and does not pay the entire cost. Your mother must use her income to pay for part of the nursing home cost & Medicaid will pay the remainder. If your mother has no income then Medicaid will pay the entire expense.