Protecting a fragment of a document includes automatically detecting the fragment without user intervention based on the content of the fragment and/or the context of the fragment within a set of documents, selectively encrypting the fragment to prevent unauthorized access, and providing an alternative view of the fragment that prevents viewing and access of content corresponding to the fragment unless a decryption password is provided. Automatically detecting the fragment may include detecting numbers and alphanumeric sequences of sufficient length that do not represent commonly known abbreviations, detecting generic terms, detecting proper names, detecting terms signifying a type of content, detecting mutual location of terms and sensitive content, and/or detecting user defined terms. The generic terms may correspond to password, passcode, credentials, user name, account, ID, login, confidential, and/or sensitive. The proper names may be names of financial organizations and security organizations.