IDOC within server and cross server

we have two server PRD1 and PRD2, we want IDOC to be sent from PRD1 to PRD2 for GL balance and account payable open item, which should be the IDOC basic type, message type and process code for both outbound parameter and inbound parameter?

when we design IDOC, if it is cross two SAP R3 server, what should be the difference in terms of IDOC design compared with sending IDOC within 1 server?