15. The method of claim 14 , further comprising: receiving the document as part of receiving a request to process the document, the request comprising one or more additional data elements; selecting an additional data element that indicates possible language for the request, the additional data element assigned to a particular weight; based on a data value of the additional data element and the particular weight, adjusting the language confidence level value for the document.
14. A data-processing method comprising: using a first computer, obtaining from one or more non-transitory computer-readable data storage media a copy of one or more sequences of instructions that are stored on the media and are arranged, when executed using a second computer among a plurality of other computers to cause the second computer to perform: using a computer, receiving an electronic document comprising a plurality of unknown-language data elements each associated with one or more types; using the computer, based on a document schema of the document, selecting one or more unknown-language data elements from the plurality of unknown-language data elements; using the computer, assigning to each of the one or more unknown-language data elements a corresponding weight value based on a respective type of the unknown-language data element; using the computer, comparing the one or more unknown-language data elements with a plurality of known-language data elements that are associated with the document schema; using the computer, based on the comparing, determining a number of unknown-language data elements in the one or more unknown-language data elements that matched any in a subset of the plurality of known-language data elements, wherein the subset of known-language data elements corresponds to a particular language; using the computer, based on the number of unknown-language data elements in the one or more unknown-language data elements that matched to the subset of known-language data elements and based on the corresponding weight value assigned to each unknown-language data element in the number of unknown-language data elements, determining a language confidence level value specifying a level of machine confidence that the document is expressed in the particular language; using the computer, based on the language confidence level value for the particular language exceeding a language threshold value, automatically processing the document using the particular language.