Stock Plans and Other Incentives - Option Activity and Other Plan Data (Detail) - $ / shares		6 Months Ended
	Dec. 31, 2014	Jun. 30, 2015	Jun. 30, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding at beginning of period, Options		582,500	627,724
Granted, Options		0	20,000
Exercised, Options		(7,500)	0
Cancelled through cash settlement, Options		0	(8,862)
Forfeited/cancelled/expired, Options		0	0
Outstanding at end of period, Options	582,500	575,000	638,862
Options exercisable at end of period, Options		559,000	618,862
Options exercisable which can be settled in cash, Options	0	0	8,862
Outstanding at beginning of period, Weighted-Average Exercise Price		$ 9.52	$ 9.05
Granted, Weighted-Average Exercise Price		0.00	18.52
Exercised, Weighted-Average Exercise Price		(7.50)	(0.00)
Cancelled through cash settlement, Weighted-Average Exercise Price		(0.00)	(4.09)
Forfeited/cancelled/expired, Weighted-Average Exercise Price		0	0
Outstanding at end of period, Weighted-Average Exercise Price	$ 9.52	9.55	9.41
Options exercisable at end of period, Weighted-Average Exercise Price		9.29	9.12
Options exercisable which can be settled in cash, Weighted-Average Exercise Price		$ 0.00	$ 4.09