Capitalization of Attorney General Office

I understand that "attorney general" by itself should not be capitalized but capitalizing attorney general should be done if it is accompanied by a name (e.g., Attorney General Stewart). But how about the actual office. Should "office of the attorney general" be capitalized as "Office of the Attorney General?" Bureau of Alcohol, or Department of Homeland Security, if I'm not mistaken, are capitalized, so I would assume Office of the Attorney General would also be capitalized.