Earnings Per Common Share - Schedule of Antidilutive Shares Excluded from Computation of Earnings Per Share (Detail) - shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Equivalent shares (if converted) (in shares)	2,019,926	980,912
Series B Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Equivalent shares (if converted) (in shares)	555,216	482,133
Series C Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Equivalent shares (if converted) (in shares)	392,727	341,032
Series D Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Equivalent shares (if converted) (in shares)	1,071,983	157,747