Beware of ISNUMERIC(), you might have some problems if you don't consider all the possibilities.
http://www.sqlservercentral.com/articles/IsNumeric/71512/
If you're using SQL Server 2012 or 2014, go for TRY_PARSE,TRY_CONVERT or TRY_CAST.
Luis C.
General Disclaimer:
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How to post data/code on a forum to get the best help: Option 1 / Option 2