Segment Information - Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Total assets:
Total assets	$ 478,233	$ 479,354
Sports segment:
Total assets:
Total assets	19,643	18,625
Energy segment:
Total assets:
Total assets	215,149	220,262
Corporate and other business activities
Total assets:
Total assets	$ 243,441	$ 240,467