Non-controlling Interest - Narrative (Details) - USD ($)		3 Months Ended		5 Months Ended		9 Months Ended
	Nov. 03, 2016	Sep. 30, 2016	Sep. 30, 2015	Aug. 31, 2016	Sep. 03, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Significant Accounting Policies [Line Items]
Exercise of stock options, Shares						28,057
Liability representing the payments due pursuant to tax receivable agreements		$ 98,782,000				$ 98,782,000
Current portion of payable pursuant to tax receivable agreements		7,225,000				$ 7,225,000		$ 8,478,000
TRA period due						12 months
Amounts paid pursuant to Tax Receivable Agreements (TRAs)						$ 1,344,000
Quarterly distribution | Subsequent Event
Significant Accounting Policies [Line Items]
Distributions declared to non-controlling unitholders	$ 1,884,000
RIHI
Significant Accounting Policies [Line Items]
Amounts paid pursuant to Tax Receivable Agreements (TRAs)						1,344,000	$ 0
RIHI | 2014 Tax Returns
Significant Accounting Policies [Line Items]
Current portion of payable pursuant to tax receivable agreements		$ 2,591,000				$ 2,591,000
RMCO, LLC
Significant Accounting Policies [Line Items]
Minority economic interest in RMCO (as a percent)		58.42%				58.42%		58.33%
Weighted average ownership percentage		58.42%	41.02%			58.39%	40.61%
Non-controlling unitholders ownership of common units in RMCO as a percentage		41.58%				41.58%		41.67%
Class A common stock | Quarterly distribution
Significant Accounting Policies [Line Items]
Distributions declared to non-controlling unitholders				$ 1,884,000	$ 2,217,000
Restricted Stock Units exchanged for Class A Common Stock [Member]
Significant Accounting Policies [Line Items]
Restricted stock, shares vested						33,288