Converting this value from Varchar to Datetime in format of YYYY-MM-DD

insert [Scorecard].[Stage].[TMP1]

      ([Key]

      ,[MemberID]

      ,[PlanID]

      ,[ADDate]

      ,[HIDDate]

SELECT

       [Key]

      ,[MemberID]

      ,[PlanID]

      , case when [ADDate]<'2078-12-31' then  [ADDate] else null end as ADDate

      , case when [HIDDate]<'2078-12-31' then [HIDDate]  else null end as HIDate            

   From Table1

My [Scorecard].[Stage].[TMP1] has data type varchar(10) for Fields [ADDate] and [HIDDate]. Intially these fields has value in format of "2012-09-05 10:27:00.000".

These 2 columns values I am getting it from another table named "Table Random".

when I am inserting into my destination table [Scorecard].[Stage].[TMP1], it comes as "Dec 31 201". I believe it is because the destination table data type is Varchar(10).

I want this value for those fields in format of YYYY-MM-DD

Thanks in advance. Any help will be appreciated.