Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE Grants (grant_start_date VARCHAR, grant_id VARCHAR)
TABLE: CREATE TABLE Document_Types (document_type_code VARCHAR, document_description VARCHAR)
TABLE: CREATE TABLE Documents (grant_id VARCHAR, document_type_code VARCHAR)

### Question ###
For grants with both documents described as 'Regular' and documents described as 'Initial Application', list its start date.

### Accurate SQL ###

SELECT T1.grant_start_date FROM Grants AS T1 JOIN Documents AS T2 ON T1.grant_id = T2.grant_id JOIN Document_Types AS T3 ON T2.document_type_code = T3.document_type_code WHERE T3.document_description = 'Regular' INTERSECT SELECT T1.grant_start_date FROM Grants AS T1 JOIN Documents AS T2 ON T1.grant_id = T2.grant_id JOIN Document_Types AS T3 ON T2.document_type_code = T3.document_type_code WHERE T3.document_description = 'Initial Application'