Wordnet 3.0
ADVERB (2)
1. 
 without warmth; 
- Example: "he treated his patients impersonally"2. 
 in an impersonal manner; 
- Example: "when I told him about Russ I found it difficult to speak impersonally"
The Collaborative International Dictionary of English v.0.48:
Impersonally \Im*per"son*al*ly\, adv.
   In an impersonal manner.
   [1913 Webster]
WordNet (r) 3.0 (2006):
impersonally
    adv 1: without warmth; "he treated his patients impersonally"
           [ant: personally]
    2: in an impersonal manner; "when I told him about Russ I found
       it difficult to speak impersonally"