From the HIPAA website:

Requests from your employer
Your employer can ask you for a doctor’s note or other health information if they need the information for sick leave, workers’ compensation, wellness programs, or health insurance.

However, if your employer asks your health care provider directly for information about you, your provider cannot give your employer the information without your authorization unless other laws require them to do so.

Generally, the Privacy Rule applies to the disclosures made by your health care provider, not the questions your employer may ask.

See 45 C.F.R. §§ 160.103 and 164.512(b)(1)(v), and OCR's Frequently Asked Questions.

For employer issues, contact:

Department of Labor: (866) 4-USA-DOL
Equal Employment Opportunity Commission: (800) 669-4000

My question:

Can the employer force you to give them detailed information if you don't want to?