1. A non-transitory computer readable medium storing a program causing a computer to execute a process for information processing, the process comprising: receiving a first characteristic value calculated on the basis of first document information for use in detecting whether tampering with the first document information has occurred; receiving a second characteristic value calculated on the basis of second document information for use in detecting whether tampering with the second document information has occurred; calculating a third characteristic value for use in detecting whether tampering with third document information has occurred on the basis of the first characteristic value, the second characteristic value and the third document information related to integration of the first document information and the second document information; and generating the third document information, indicating integration of the first document information and the second document information when an instruction to integrate the first document information and the second document information is received, wherein the third document information is generated to include first user information for identifying a first user that initiated the integration of the first document information and the second document information, and wherein the third document information comprises: an execution request document created in response to the first user initiating the integration of the first document information and the second document information; and an execution confirmation document created in response to a second user confirming the integration of the first document information and the second document information initiated by the first user.
1. A non-transitory computer readable medium storing a program causing a computer to execute a process for information processing, the process comprising: receiving a first characteristic value calculated on the basis of first document information for use in detecting whether tampering with the first document information has occurred; receiving a second characteristic value calculated on the basis of second document information for use in detecting whether tampering with the second document information has occurred; calculating a third characteristic value for use in detecting whether tampering with third document information has occurred on the basis of the first characteristic value, the second characteristic value and the third document information related to integration of the first document information and the second document information; and generating the third document information, indicating integration of the first document information and the second document information when an instruction to integrate the first document information and the second document information is received, wherein the third document information is generated to include first user information for identifying a first user that initiated the integration of the first document information and the second document information, and wherein the third document information comprises: an execution request document created in response to the first user initiating the integration of the first document information and the second document information; and an execution confirmation document created in response to a second user confirming the integration of the first document information and the second document information initiated by the first user. 2. The non-transitory computer readable medium according to claim 1 , wherein the third document information is generated to include an indication that a subject of the second document information is a subject of the first document information.