A Study to Test How a New Long-acting Insulin (Insulin Icodec) Works in the Body of People With Liver Disease

Inclusion Criteria: * Male or female * Aged 18-70 years (both inclusive) at the time of signing informed consent * Body mass index between 18.5 and 39.9 kg/m\^2 (both inclusive) Specific inclusion criterion only for subjects with hepatic impairment * Subjects with stable hepatic impairment classified as Child-Pugh grade A, B or C as assessed by the investigator. Stable hepatic impairment is defined as no clinically significant change in disease status, as judged by the investigator. Exclusion Criteria: * Known or suspected hypersensitivity to trial product or related products * Female who is pregnant, breast-feeding or intends to become pregnant or is of child-bearing potential and not using an adequate contraceptive method (adequate contraceptive measures as required by local regulation or practice) * Diagnosis of diabetes mellitus