Changes in the carrying amount of goodwill are as follows (in thousands):
 
As of December 31,
 
2016
 
2015
Beginning of period
$
738,200

 
$
186,895

Goodwill acquired
2,258

 
650,289

Goodwill impairment

 
(99,145
)
Purchase accounting adjustment (1)
(951
)
 
161

Ending balance
$
739,507

 
$
738,200


(1) The 12/31/2016 adjustment represents an adjustment to the purchase price allocation resulting in an increase to deferred tax assets and a reduction of goodwill.