According to Delta's Travelnet there are three L (Landing) fees for the US.
$5
$5
$7


Just coming back from CPH sunday the fees are shown as

$21.78 Danish Departure Fee
$5.00 US Landing Fee
$5.00 US Landing Fee
$7.00 US Landing Fee

$38.78 total.

Hope it helps.
Tchau

DA-