CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY - USD ($) $ in Thousands	Total	Cumulative effect adjustment	Cumulative Effect, Period of Adoption, Adjusted Balance	Total Stockholders' Equity	Total Stockholders' Equity Cumulative effect adjustment	Total Stockholders' Equity Cumulative Effect, Period of Adoption, Adjusted Balance	Treasury Stock	Treasury Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Accumulated Other Comprehensive Loss	Accumulated Other Comprehensive Loss Cumulative Effect, Period of Adoption, Adjusted Balance	Additional Paid-in Capital	Additional Paid-in Capital Cumulative Effect, Period of Adoption, Adjusted Balance	Retained Earnings (Deficit)	Retained Earnings (Deficit) Cumulative effect adjustment	Retained Earnings (Deficit) Cumulative Effect, Period of Adoption, Adjusted Balance	Non-controlling Interest	Non-controlling Interest Cumulative Effect, Period of Adoption, Adjusted Balance	Class A Common Stock Common Stock	Class A Common Stock Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance	Class B Common Stock	Class B Common Stock Common Stock	Class B Common Stock Common Stock Cumulative Effect, Period of Adoption, Adjusted Balance
Balance at beginning of period (in shares) at Dec. 31, 2018							99,000											14,178,000			20,800,000
Balance at beginning of period at Dec. 31, 2018	$ 90,294			$ 45,806			$ (2,011)		$ 2		$ 46,157		$ 1,307			$ 44,488		$ 142			$ 209
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation (in shares)																		301,000
Stock based compensation	2,511			2,511							2,511
Restricted stock unit vesting	(1,104)			(1,104)							(1,107)							$ 3
Consolidated net income	(22,739)			(6,333)									(6,333)			(16,406)
Impact of adoption of ASC 606	(98)			(40)					(40)							(58)
Distributions paid to non-controlling unit holders	(7,978)															(7,978)
Dividends paid to Class A common stockholders (in dollars per share)	(5,170)			(5,170)							(5,170)
Dividends paid to Preferred Stockholders	(4,056)			(4,056)							(2,029)		(2,027)
Changes in ownership interest				1,912							1,912					(1,912)
Proceeds from disgorgement of stockholder short-swing profits	55			55							55
Acquisition of Customers from Affiliate	(10)															(10)
Balance at end of period (in shares) at Jun. 30, 2019							99,000											14,479,000			20,800,000
Balance at end of period at Jun. 30, 2019	51,705			33,581			$ (2,011)		(38)		42,329		(7,053)			18,124		$ 145			$ 209
Balance at beginning of period (in shares) at Mar. 31, 2019							99,000											14,241,000			20,800,000
Balance at beginning of period at Mar. 31, 2019	85,750			44,159			$ (2,011)		(12)		45,769		62			41,591		$ 142			$ 209
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation (in shares)																		238,000
Stock based compensation	1,440			1,440							1,440
Restricted stock unit vesting	(1,104)			(1,104)							(1,107)		0			0		$ 3
Consolidated net income	(25,484)			(7,115)									(7,115)			(18,369)
Impact of adoption of ASC 606	(63)			(26)					(26)							(37)
Distributions paid to non-controlling unit holders	(4,208)															(4,208)
Dividends paid to Class A common stockholders (in dollars per share)	(2,606)			(2,606)							(2,606)
Dividends paid to Preferred Stockholders	(2,029)			(2,029)							(2,029)
Changes in ownership interest				853							853					(853)
Proceeds from disgorgement of stockholder short-swing profits	9			9							9
Balance at end of period (in shares) at Jun. 30, 2019							99,000											14,479,000			20,800,000
Balance at end of period at Jun. 30, 2019	51,705			33,581			$ (2,011)		(38)		42,329		(7,053)			18,124		$ 145			$ 209
Balance at beginning of period (in shares) at Dec. 31, 2019							99,000											14,479,000			20,800,000
Balance at beginning of period at Dec. 31, 2019	67,286	$ (633)	$ 66,653	51,219	$ (633)	$ 50,586	$ (2,011)	$ (2,011)	(40)	$ (40)	51,842	$ 51,842	1,074	$ (633)	$ 441	16,067	$ 16,067	$ 145	$ 145		$ 209	$ 209
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation	1,772			1,772							1,772
Restricted stock unit vesting (in shares)																		293,000
Restricted stock unit vesting	(912)			(912)							(915)							$ 3
Consolidated net income	36,845			15,638												21,207
Impact of adoption of ASC 606	0
Distributions paid to non-controlling unit holders	(13,735)															(13,735)				$ (7,500)
Dividends paid to Class A common stockholders (in dollars per share)	(5,265)			(5,265)									(5,265)
Dividends paid to Preferred Stockholders	(3,539)			(3,539)									(3,539)
Changes in ownership interest				710							710					(710)
Balance at end of period (in shares) at Jun. 30, 2020							99,000											14,772,000			20,800,000
Balance at end of period at Jun. 30, 2020	81,819			58,990			$ (2,011)		(40)		53,409		7,275			22,829		$ 148			$ 209
Balance at beginning of period (in shares) at Mar. 31, 2020							99,000											14,495,000			20,800,000
Balance at beginning of period at Mar. 31, 2020	66,733			51,827			$ (2,011)		(40)		52,710		814			14,906		$ 145			$ 209
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock based compensation	443			443							443
Restricted stock unit vesting (in shares)																		277,000
Restricted stock unit vesting	(873)			(873)							(876)							$ 3
Consolidated net income	26,777			11,159									11,159			15,618
Impact of adoption of ASC 606
Distributions paid to non-controlling unit holders	(6,563)															(6,563)
Dividends paid to Class A common stockholders (in dollars per share)	(2,659)			(2,659)									(2,659)
Dividends paid to Preferred Stockholders	(2,039)			(2,039)									(2,039)
Changes in ownership interest				1,132							1,132					(1,132)
Balance at end of period (in shares) at Jun. 30, 2020							99,000											14,772,000			20,800,000
Balance at end of period at Jun. 30, 2020	$ 81,819			$ 58,990			$ (2,011)		$ (40)		$ 53,409		$ 7,275			$ 22,829		$ 148			$ 209