Discontinued Operations (Assets and Liabilities of Discontinued Operations) (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Assets of Discontinued Operations:
Receivables, net of allowance for bad debt	$ 1,276	$ 4,632
Oil and gas properties and equipment, net	438	79,733
Goodwill and other intangible assets	0	19,673
Prepaid expenses	31	96
Other assets	100	833
Assets of discontinued operations	1,845	104,967
Liabilities of Discontinued Operations:
Accounts payable	751	342
Accrued property taxes	0	259
Other accrued expenses	1,979	8,924
Other liabilities	386	1,667
Liabilities held for sale	$ 3,116	$ 11,192