Query Question

I have created 3 tables, the parent table has a primary key(pmt_id) which is generated by a sequence object which is tied to this table.  The 2^nd table paid_policy is a child to the first table and has a primary key of pmt_id, (which is the FK to the 1^st table), plcy_num and rqst_id.  The third table which is a child to the 2^nd table has a primary key of pmt_id, plcy_num, rqst_id, and pmt_tstmp.  When inserting a row into the parent the sequence number is generated and returned by the statement below; however, I have not been able to figure out a way to capture this id to insert it in the 3^rd table since it is part of the key.  This application will have thousands if not hundreds of thousands of inserts daily, so I was concerned that current value could change.  I thought about trying to capture the rowid from the statement below but was wondering if there is a better way to accomplish this.  Any assistance would be greatly appreciated.  I just joined the mailing list within the last hour so I am very new at this.  Thanks in advance.

WITH testtbl AS (

INSERT INTO schema.pmt_wip

     (pmt_id, clnt_id, agt_assoc_id, pmt_stts_cd, refr_num, user_id, pmt_rcpt_tstmp)

VALUES

     (nextval('schema.pmt_wip_seq'), 'Client ID 5', 'Assoc Id 6', 1, 'reference number', 'PCPA', Now())

RETURNING pmt_id

)  INSERT INTO schema.paid_plcy

        (pmt_id, plcy_num, rqst_id, plcy_st_cd, co_code, addl_life_plcy_amt, prem_trf_amt)

   VALUES

        ((SELECT pmt_id FROM testtbl), 'policy #2', 'rqst id2', 25, 4, 0, 0);