Equity-Based Compensation - Activity with Respect to SARs (Detail) - $ / shares	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of shares, issued and unvested end of period (in shares)	479,656
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Number of shares issued	0	1,869
SARs
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of shares, issued and unvested beginning of period (in shares)	479,656	548,482	548,482
Number of shares, granted (in shares)	0	1,500
Number of shares, exercised	0	(7,897)
Number of shares, forfeited	0	0
Number of shares, issued and unvested end of period (in shares)	479,656	542,085	479,656
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Weighted Average Base Price [Roll Forward]
Weighted average base price, beginning of period	$ 10.64	$ 10.62	$ 10.62
Weighted average base price, granted	0.00	16.69
Weighted average base price, exercised	0.00	10.61
Weighted average base price, forfeited	0.00	0.00
Weighted average base price, end of period	10.64	10.64	10.64
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average fair value, beginning of period	5.80	5.79	5.79
Weighted average fair value, granted (in dollars per share)	0.00	8.99
Weighted average fair value, exercised	0.00	5.72
Weighted average fair value, forfeited (in dollars per share)	0.00	0.00
Weighted average fair value, end of period	$ 5.80	$ 5.80	$ 5.80