diff --git a/talon/utils.py b/talon/utils.py
index ebabdf1..02a7a92 100644
--- a/talon/utils.py
+++ b/talon/utils.py
@@ -47,8 +47,8 @@ def to_unicode(str_or_unicode, precise=False):
         u'привет'
     If `precise` flag is True, tries to guess the correct encoding first.
     """
-    encoding = quick_detect_encoding(str_or_unicode) if precise else 'utf-8'
     if not isinstance(str_or_unicode, six.text_type):
+        encoding = quick_detect_encoding(str_or_unicode) if precise else 'utf-8'
         return six.text_type(str_or_unicode, encoding, 'replace')
     return str_or_unicode