In what category would the following go under

Received $12,000 cash from customers for contract billed in April

In what category would the following go under

Received $12,000 cash from customers for contract billed in April
Assuming you billed customer "ABC" in April 2007 for total contract amount of, say $50,000.

Your entry in April should have been:

Dr. Accounts Receivable - (Customer ABC) $50,000
Cr. Contract Revenue $50,000
To record completed contract with Customer ABC

Your Current Entry should be:

Dr. Cash $12,000
Cr. Accounts Receivable - (Customer ABC) $12,000

Hope this helps!