Attribute Validation without AttributeValidator (integer regex)

Hi,

I am using FME Desktop 2015.1 and need to test an attribute field for integer status.

passes are any whole number including;

zero

negative numbers where prefixed with "-"

positive numbers where NOT prefixed with "-"

In the absence of having attributeValidator (2016) can anyone advise me of the correct regex string?

Does ^(\\-)?\\d+$ look correct?

Thanks in advance,

Rob