$Group = (Get-Content -Path C:UsersmyusernameDocumentstestlist.txt)

$Table = @()

$Record = [ordered] @{
"Group Name" = ""
"Name" = ""
"Username" = ""
}

foreach ($Group in $Groups)
{

$Arrayofmembers = Get-ADGroupMember -Identity -Group|selectname,samaccountname

foreach ($Member in $Arrayofmembers)
{
$Record."Group Name" = $Group
$Record."Name" = $Member.name
$Record."Username" = $Member.samaccountname
$objRecord = New-Object psobject -Property $Record
$Table += $objrecord

}

}

$Table |export-csv "C:usersmyusernameDocumentssecuritygroups.csv"    -NoTypeInformation