This case-sensitive code system http://hl7.org/fhir/us/davinci-pdex-plan-net/CodeSystem/OrgTypeCS defines the following codes:

Code	Display	Definition
fac	Facility	A physical healthcare facility.
prvgrp	Provider Group	A healthcare provider entity
payer	Payer	A healthcare payer.
atyprv	Atypical Provider	Providers that do not provide healthcare
bus	Non-Healthcare Business	An organization that does not meet the definitions of a Healthcare or Atypical Provider, and is not a payer or healthcare facility
ntwk	Network	A healthcare provider insurance network