Overview

Create an abstract data structure and service schema for standard accounting requirements.

General Ledger account structure

The General Ledger is a list of Control Accounts and Sub-Accounts, Control Accounts move it's transactions and account heirachy to a Subsidiary Ledger, so they do not clutter the General Ledger.
Control Accounts only exist as a child of the General Ledger, and only exist as a bridge to Subsidiary Ledgers
other Accounts can be called different things, when they form the heirachy shown in the General Ledger they are normally called Sub-Accounts, when in a Subsidiary Ledger they have many names, often Subsidiary Accounts

Transactions occur in Accounts
Transactions by accounting norms can only be added to Accounts that have no child Accounts (leaf Accounts)

Subsidiary Ledgers in normal General Ledgers only exist at the top level
Subsidiary Ledger is simply a method of hiding detail from the General Ledger, but ultimately continues an account heirachy
The entire structure is a heirachy of accounts
Transactions roll up the heirachy tree combining until their total is added to the General Ledger in a top level Control/Sub-Account

create a tree of accounts only
create a ledger config/report system that specifies which accounts in the heirachy are hidden, only their total will be shown
by setting a range of top level accounts to be hidden you effectively create Subsidiary Ledgers and can mimic a General Ledger report
this would allow a more powerful method of created General Ledeger-like reports that can collapse accounts at any level to only show their totals
within that config is a method of automatically creating the Control Accounts, which is simply a final total of a collapsed account

do not allow Transactions to be added to non-leaf Accounts, do not allow Accounts to be added to Accounts that have existing Transactions
or if it does not increase complexity have a setting (default false) whether to allow shared Transactions and Accounts under a single Account