You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Seattle

Context:
Seattle remained the corporate headquarters of Boeing until 2001, when the company separated its headquarters from its major production facilities; the headquarters were moved to Chicago. The Seattle area is still home to Boeing's Renton narrow-body plant (where the 707, 720, 727, and 757 were assembled, and the 737 is assembled today) and Everett wide-body plant (assembly plant for the 747, 767, 777, and 787). The company's credit union for employees, BECU, remains based in the Seattle area, though it is now open to all residents of Washington.

Question:
What did Boeing separate from its headquarters facilities?

production facilities