Attach and Detach Databases

----- 1: ATTACH DATABASES
EXEC sp_attach_db @dbname = N'DBName'
, @filename1 = N'X:\LocalfilePath\DataFileName.MDF'
, @filename2 = N'X:\LocalfilePath\LogFileName..LDF'

----- 2: RESTORE DATABASES
RESTORE DATABASE DBName WITH RECOVERY

----- 3: DETACH DATABASES
EXEC sp_detach_db 'DBName', 'TRUE'

To generate Detach Statement for all User Databases on particular SQL Instance:
SET QUOTED_IDENTIFIER OFF
SELECT
"EXEC sp_detach_db '" + Name + "', " +"'TRUE'"
FROM
master..sysdatabases
WHERE
DBID > 4
SET QUOTED_IDENTIFIER ON

Then Execute each Detach Database SQL Statement in Query Analyzer