NAMPA -- A Nampa man pleaded not guilty Thursday to beating, stabbing and strangling his elderly parents and hiding their bodies in a shed.

William "Willie" Paul Taylor, 48, remains held in the Canyon County Jail on a $1 million bond. He faces two counts of murder and two counts of failure to notify authorities of a death in connection to the slayings of 76-year-old Paul Robert Taylor and 77-year-old Mary Jane Taylor.

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Investigators say they believe the couple was killed sometime around Sept. 9, although their remains were not discovered until five days later, when someone noticed a foul odor coming from a shed behind the Taylors' Flamingo Road home.

Detectives say Mary Jane Taylor, whose body was found wrapped up in a blue tarp, had been beaten, stabbed 10 times and had her throat slashed. Her husband had been strangled and hit multiple times in the head with some sort of blunt object, leaving him with massive skull fractures.

Willie Taylor, who had been living with his parents, was gone, along with his father's pickup. Deputies with the Deschutes County Sheriff's Office caught up to him the night of Sept. 14, after spotting the missing pickup at a rest stop near Terrebonne, Oregon.

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According to court documents, Taylor told deputies that he had not killed his parents, but had come home to find them both dead. The suspect added that he had tried to clean up and move the bodies, but neglected to call 911 because he had been drinking.

Taylor said he "was afraid and didn't know what to do after he found his parents, so he took his dad's truck and left," according to a probable cause affidavit.

Nampa Police found pools of blood and drag marks inside the house, along with evidence that Taylor had tried to wash off a patio and discard bloodstained clothing, towels and tarps.

Inside the suspect's room, investigators also found a hand-written to-do list which included the items "Shave, Shower, City Council, Crime." Taylor was captured on surveillance video at local stores Sept. 10 and 11 buying cleaning supplies, trash bags, duct tape and a brass padlock.

Taylor was extradited back to Idaho in October to face charges, and is due back in court Nov. 27 for a scheduling hearing.

If convicted, he could face up to life in prison or the death penalty.