Shareholders' Equity / Partners' Capital (Tables)

3 Months Ended

Mar. 31, 2019

Equity [Abstract]

Schedule of Preferred Shares Outstanding

As of March 31, 2019, and December 31, 2018, the Company had the following series of preferred shares outstanding (in thousands, except share data):

					March 31, 2019			December 31, 2018
Series	Issuance Date	Earliest Redemption Date	Dividend Rate		Outstanding Shares	Current Liquidation Value		Outstanding Shares	Current Liquidation Value
Series D perpetual preferred shares	5/24/2016	5/24/2021	6.500	%	10,750,000	268,750		10,750,000	268,750
Series E perpetual preferred shares	6/29/2016	6/29/2021	6.350	%	9,200,000	230,000		9,200,000	230,000
Series F perpetual preferred shares	4/24/2017	4/24/2022	5.875	%	6,200,000	155,000		6,200,000	155,000
Series G perpetual preferred shares	7/17/2017	7/17/2022	5.875	%	4,600,000	115,000		4,600,000	115,000
Series H perpetual preferred shares	9/19/2018	9/19/2023	6.250	%	4,600,000	115,000		4,600,000	115,000
Total preferred shares					35,350,000	$	883,750	35,350,000	$	883,750

Noncontrolling Interest Activity in Condensed Consolidated Statements of Operations

The following table summarizes the income or loss allocated to noncontrolling interests as reflected in the Company's condensed consolidated statements of operations for the three months ended March 31, 2019 and 2018 (in thousands):

	For the Three Months Ended
	March 31, 2019		March 31, 2018
Net income allocated to Class A units	$	3,026	$	1,125
Net income (loss) allocated to noncontrolling interest in a consolidated subsidiary	—		(11		)
Total noncontrolling interest	$	3,026	$	1,114

Summary of Stock Option Activity under Plan

The following table summarizes stock option activity under the Plan for the three months ended March 31, 2019 and 2018:

	Shares		Weighted-Average Exercise Price		Weighted-Average Remaining Contractual  Life (in years)	Aggregate Intrinsic Value (1) (in thousands)
Options outstanding at January 1, 2018	3,052,450		$	16.65	6.9	$	16,421
Granted	140,000		19.40
Exercised	(7,500	)	16.62			22
Forfeited	(10,000	)	17.83
Options outstanding at March 31, 2018	3,174,950		$	16.76	6.7	$	11,748
Options exercisable at March 31, 2018	2,272,675		$	16.16	6.1	$	9,213
Options outstanding at January 1, 2019	2,252,275		$	16.92	6.1	$	7,713
Granted	20,000		20.48
Exercised	(5,000	)	14.00			35
Forfeited	(9,850	)	22.53
Options outstanding at March 31, 2019	2,257,425		$	16.93	5.9	$	13,267
Options exercisable at March 31, 2019	1,867,025		$	16.41	5.5	$	11,872

(1) Intrinsic value for activities other than exercises is defined as the difference between the grant price and the market value on the last trading day of the period for those stock options where the market value is greater than the exercise price. For exercises, intrinsic value is defined as the difference between the grant price and the market value on the date of exercise.

Summary of Black-Scholes Option Pricing Model Inputs used for Valuation of Stock Options Outstanding

The following table summarizes the Black-Scholes Option Pricing Model inputs used for valuation of the stock options for Class A common shares granted during the three months ended March 31, 2019 and 2018:

	2019			2018
Weighted-average fair value	$	2.85		$	3.03
Expected term (years)		7.0			7.0
Dividend yield		3.0	%		3.0	%
Volatility		17.3	%		18.9	%
Risk-free interest rate		2.6	%		2.8	%

Summary of Restricted Stock Units Activity Under Plan

The following table summarizes the activity that relates to the Company’s restricted stock units under the Plan for the three months ended March 31, 2019 and 2018:

	2019		2018
Restricted stock units at beginning of period	372,375		243,875
Units awarded	317,950		304,400
Units vested	(110,650	)	(79,525	)
Units forfeited	(5,400	)	(5,625	)
Restricted stock units at end of period	574,275		463,125