SQL & PL/SQL :: Session Aborted After Closing Window?

I created following table and procedure

create table t(n number);
create or replace procedure prc as
begin
insert into t values (1);
commit;
sys.dbms_lock.sleep(10);

[code]...

I opened 2 sessions

from session -1, I executed

exec prc

from session -2, I executed

select * from t;

In the middle of the execution when I had following values inserted into t, I closed the sql window of session where I was executing the process prc

select * from t;
n
--------
1
2
3

and found that the session got terminated and no values inserted into table t after this.

I may be missing some basic oracle stuff here but I was expecting the session would continue running on the server inserting values in table t upto 6.

I would like to know in which case a session executed from sql client will continue even while the sql window is closed?