在三棱锥 A−BCDA - {BCD}A−BCD 中,已知 BC=CD=BD=2AB=2AD=6{BC} = {CD} = {BD} = \sqrt{2}{AB} = \sqrt{2}{AD} = 6BC=CD=BD=2AB=2AD=6 , 且平面 ABD⊥{ABD} \botABD⊥ 平面 BCD{BCD}BCD ,则三棱锥 A−BCDA - {BCD}A−BCD 外接球的表面积为___.