(AP) -- DETROIT - The Detroit Medical Center says it's extending its deadline by 10 days to reach a binding definitive agreement to be purchased by a private Nashville, Tenn.-based health system.

The nonprofit Detroit health system said in a statement Monday the extension is "routine but necessary" to complete the required legal work in the deal with Vanguard Health Systems.

Additional work includes archival document searches and review for some DMC properties.

The original deadline to reach the agreement was Monday.

The eight-hospital system and Vanguard in March signed a letter of intent for the sale. Terms include Vanguard making $850 million in capital improvements during the next five years.

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