Segment Information - Assets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Total assets:
Total assets	$ 474,098	$ 479,354
Sports segment:
Total assets:
Total assets	18,559	18,625
Energy segment:
Total assets:
Total assets	220,068	220,262
Corporate and other business activities
Total assets:
Total assets	$ 235,471	$ 240,467