[Regular expression] how can I "match to end or end with a string", for example, MV & id = 17328895840 & scm = 102 and MV & id = 17328895840 can both be matched?

[Regular expression] how to & quot; match to end or end with a string & quot ;. for example, both MV & amp; id = 17328895840 & amp; scm = 102 and MV & amp; id = 17328895840 can be matched. example: str & nbsp ;=& nbsp; M [regular expression] ask how to "match to end or end with a string ". for example, both MV & id = 17328895840 & scm = 102 and MV & id = 17328895840 can be matched.
Example:

Str = MV & id = 17328895840 & scm = 102

Reg = "/& id = (./) &/U ";

You can get 17328895840

However, MV & id = 17328895840 cannot be matched.

I tried reg = "/& id = (./) [& | $]/U ";

I want to teach you how to write regular expressions to match both of them at the same time.

Thank you.
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$ Reg = "/& id = (. + )(? :&
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$)/U ";
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$ Reg = "/& id = (. + ?) (&
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$ )/";