diff --git a/Lib/idlelib/ColorDelegator.py b/Lib/idlelib/ColorDelegator.py
index 7f4d740..0610c4b 100644
--- a/Lib/idlelib/ColorDelegator.py
+++ b/Lib/idlelib/ColorDelegator.py
@@ -20,10 +20,11 @@
     # 1st 'file' colorized normal, 2nd as builtin, 3rd as string
     builtin = r"([^.'\"\\#]\b|^)" + any("BUILTIN", builtinlist) + r"\b"
     comment = any("COMMENT", [r"#[^\n]*"])
-    sqstring = r"(\b[rRuU])?'[^'\\\n]*(\\.[^'\\\n]*)*'?"
-    dqstring = r'(\b[rRuU])?"[^"\\\n]*(\\.[^"\\\n]*)*"?'
-    sq3string = r"(\b[rRuU])?'''[^'\\]*((\\.|'(?!''))[^'\\]*)*(''')?"
-    dq3string = r'(\b[rRuU])?"""[^"\\]*((\\.|"(?!""))[^"\\]*)*(""")?'
+    stringprefix = r"(\br|u|ur|R|U|UR|Ur|uR|b|B|br|Br|bR|BR)?"
+    sqstring = stringprefix + r"'[^'\\\n]*(\\.[^'\\\n]*)*'?"
+    dqstring = stringprefix + r'"[^"\\\n]*(\\.[^"\\\n]*)*"?'
+    sq3string = stringprefix + r"'''[^'\\]*((\\.|'(?!''))[^'\\]*)*(''')?"
+    dq3string = stringprefix + r'"""[^"\\]*((\\.|"(?!""))[^"\\]*)*(""")?'
     string = any("STRING", [sq3string, dq3string, sqstring, dqstring])
     return kw + "|" + builtin + "|" + comment + "|" + string +\
            "|" + any("SYNC", [r"\n"])
diff --git a/Misc/NEWS b/Misc/NEWS
index e99efca..8bfa569 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -430,6 +430,9 @@
 - Issue #12157: Make pool.map() empty iterables correctly.  Initial
   patch by mouad.
 
+- Issue #14958: Change IDLE systax highlighting to recognize all string and byte
+  literals currently supported in Python 2.7.
+
 - Issue #14962: Update text coloring in IDLE shell window after changing
   options.  Patch by Roger Serwy.