Transact SQL :: Find Missing Months In A Table For The Earliest And Latest Start Dates Per ID Number?

I need to find the missing months in a table for the earliest and latest start dates per ID_No.  As an example:

create table #InputTable (ID_No int ,OccurMonth datetime)
insert into #InputTable (ID_No,OccurMonth) 
select 10, '2007-11-01' Union all
select 10, '2007-12-01' Union all
select 10, '2008-01-01' Union all
select 20, '2009-01-01' Union all
select 20, '2009-02-01' Union all
select 20, '2009-04-01' Union all
select 30, '2010-05-01' Union all
select 30, '2010-08-01' Union all
select 30, '2010-09-01' Union all
select 40, '2008-03-01'

For the above table, the answer should be:

ID_No OccurMonth
----- ----------
20 2009-02-01
30 2010-06-01
30 2010-07-01

1) don't include an ID column,

2) don't use the start date/end dates in the data or

3) use cursors, which are forbidden in my environment.