id

The ID used to identify the key. For an Amazon Web Services KMS key, you can use the key ID, the key ARN, or the alias ARN.

Aliases are recognized only in the account that created the KMS key. For cross-account actions, you can only use the key ID or key ARN to identify the key. Cross-account actions involve using the role from the other account (AccountB), so specifying the key ID will use the key from the other account (AccountB).