Income Taxes - Summary of Reconciles Provision for Income Taxes (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation of federal statutory tax rate to effective rate
Statutory U.S. federal income tax rate	35.00%	35.00%	35.00%
Income passed through to Partners	(12.43%)	(12.43%)	(25.57%)
State and local income taxes	18.50%	15.60%	6.92%
Permanent items	(2.18%)	(3.69%)	(0.00%)
Life insurance proceeds	(0.00%)	(0.00%)	(5.41%)
Other	(0.29%)	2.87%	0.13%
Effective income tax rate	38.60%	37.35%	11.07%