If you want to remove any text up to and including the first comma you could do this.

$ perl -Mstrict -Mwarnings -e '
open my $inFH, q{<}, \ <<EOD or die $!;
L1,830 HORIZON PKG RELEASE
L2,
L3,PURPOSE:,00,RELEASE #,746962464,SCHEDULE TYPE:,PR,
L4,SCH QTY TYPE:,A,
L5,
L6,HORIZON START:,20140915
L7,END:,20150913
L8,GENERATION DATE:,20140915
L9,
L10,SHIP TO NAME:,,
L16,SHIP TO CODE:,US08,
L15,
DETAIL,BUYERS PART #,QUANTITY,FCST TYPE,FCST TIMING,DATE,   
DETAIL,1070954,6000,PLANNING(D),DISCREET(D),20140925SMS,10,
DETAIL,1070954,10000,PLANNING(D),DISCREET(D),20140926SMS,10,
EOD

while ( <$inFH> )
{                                         
    s{^[^,]*,}{};
    print
}                  
                      
close $inFH or die $!;'
830 HORIZON PKG RELEASE

PURPOSE:,00,RELEASE #,746962464,SCHEDULE TYPE:,PR,
SCH QTY TYPE:,A,

HORIZON START:,20140915
END:,20150913
GENERATION DATE:,20140915

SHIP TO NAME:,,
SHIP TO CODE:,US08,

BUYERS PART #,QUANTITY,FCST TYPE,FCST TIMING,DATE,   
1070954,6000,PLANNING(D),DISCREET(D),20140925SMS,10,
1070954,10000,PLANNING(D),DISCREET(D),20140926SMS,10,
$
[download]

If you ony want to remove the particular fields you mention in your code then you can construct a regex with alternation.

$ perl -Mstrict -Mwarnings -e '
open my $inFH, q{<}, \ <<EOD or die $!;
L1,830 HORIZON PKG RELEASE
L2,
L3,PURPOSE:,00,RELEASE #,746962464,SCHEDULE TYPE:,PR,
L4,SCH QTY TYPE:,A,
L5,
L6,HORIZON START:,20140915
L7,END:,20150913
L8,GENERATION DATE:,20140915
L9,
L10,SHIP TO NAME:,,
L16,SHIP TO CODE:,US08,
L15,
DETAIL,BUYERS PART #,QUANTITY,FCST TYPE,FCST TIMING,DATE,   
DETAIL,1070954,6000,PLANNING(D),DISCREET(D),20140925SMS,10,
DETAIL,1070954,10000,PLANNING(D),DISCREET(D),20140926SMS,10,
EOD

my @removes = map { q{L} . $_ } 1 .. 12, 14 .. 16;
push @removes, qw{ DETAIL SPACE SUMMARY };
                 
my $qrRemove = do {
   local $" = q{|};
   qr{^(?:@removes),};
   };                  

while ( <$inFH> )
{
    s{$qrRemove}{};
    print
}

close $inFH or die $!;'
830 HORIZON PKG RELEASE

PURPOSE:,00,RELEASE #,746962464,SCHEDULE TYPE:,PR,
SCH QTY TYPE:,A,

HORIZON START:,20140915
END:,20150913
GENERATION DATE:,20140915

SHIP TO NAME:,,
SHIP TO CODE:,US08,

BUYERS PART #,QUANTITY,FCST TYPE,FCST TIMING,DATE,   
1070954,6000,PLANNING(D),DISCREET(D),20140925SMS,10,
1070954,10000,PLANNING(D),DISCREET(D),20140926SMS,10,
$
[download]

I hope this is helpful.