Description of the business: (Tables)

9 Months Ended

Sep. 30, 2020

Description of the business and recent developments:

Schedule of diluted weighted average shares

	Three Months Ended	Three Months Ended	Nine Months Ended	Nine Months Ended
	September 30, 2020	September 30, 2019	September 30, 2020	September 30, 2019
Weighted average common shares - basic	45,815,718	45,438,656	45,818,677	45,428,305
Dilutive effect of stock options	—	34,593	99,581	32,179
Dilutive effect of restricted stock	—	546,442	680,612	487,847
Weighted average common shares - diluted	45,815,718	46,019,691	46,598,870	45,948,331

Schedule of unvested and anti-dilutive shares

	Three Months	Three Months	Nine Months	Nine Months
	Ended	Ended	Ended	Ended
	September 30, 2020	September 30, 2019	September 30, 2020	September 30, 2019
Unvested shares of restricted common stock	1,472,572	1,379,446	1,472,572	1,379,446
Anti-dilutive options for common stock	87,214	37,606	24,453	50,928
Anti-dilutive shares of restricted common stock	925,866	—	191	50,292

Schedule of Stockholders' Deficit

The following details the changes in stockholders’ deficit for the three and nine months ended September 30, 2020 and September 30, 2019 (in thousands except share amounts):

						Accumulated
				Additional		Other				Total
	Common Stock			Paid-in		Comprehensive		Accumulated		Stockholders’
	Shares	Amount		Capital		Income (Loss)		Deficit		Equity (Deficit)
Balance at June 30, 2020	47,279,201	$	47	$	506,391	$	(12,906)	$	(729,082)	$	(235,550)
Forfeitures of shares granted to employees	(4,932)		—		—		—		—		—
Equity-based compensation	—		—		7,147		—		—		7,147
Foreign currency translation	—		—		—		5,408		—		5,408
Issuances of common stock	10,500		—		—		—		—		—
Exercises of options	4,134		—		185		—		—		185
Common stock purchases and retirement	(4,567)		—		(269)		—		—		(269)
Dividends paid	—		—		—		—		(32,657)		(32,657)
Net loss	—		—		—		—		(4,955)		(4,955)
Balance at September 30, 2020	47,284,336	$	47	$	513,454	$	(7,498)	$	(766,694)	$	(260,691)

						Accumulated
				Additional		Other				Total
	Common Stock			Paid-in		Comprehensive		Accumulated		Stockholders’
	Shares	Amount		Capital		Income (Loss)		Deficit		Equity (Deficit)
Balance at June 30, 2019	46,806,370	$	47	$	481,734	$	(10,967)	$	(647,404)	$	(176,590)
Forfeitures of shares granted to employees	(4,508)		—		—		—		—		—
Equity-based compensation	—		—		5,311		—		—		5,311
Foreign currency translation	—		—		—		(4,709)		—		(4,709)
Issuances of common stock	10,572		—		—		—		—		—
Exercises of options	9,152		—		351		—		—		351
Dividends paid	—		—		—		—		(28,565)		(28,565)
Net income	—		—		—		—		13,701		13,701
Balance at September 30, 2019	46,821,586	$	47	$	487,396	$	(15,676)	$	(662,268)	$	(190,501)

						Accumulated
				Additional		Other				Total
	Common Stock			Paid-in		Comprehensive		Accumulated		Stockholders'
	Shares	Amount		Capital		Income (Loss)		Deficit		Equity (Deficit)
Balance at December 31, 2019	46,840,434	$	47	$	493,178	$	(12,326)	$	(684,578)	$	(203,679)
Forfeitures of shares granted to employees	(42,212)		—		—		—		—		—
Equity-based compensation	—		—		19,371		—		—		19,371
Foreign currency translation	—		—		—		4,828		—		4,828
Issuances of common stock	465,530		—		—		—		—		—
Exercises of options	25,151		—		1,174		—		—		1,174
Common stock purchases and retirement	(4,567)		—		(269)		—		—		(269)
Dividends paid	—		—		—		—		(94,952)		(94,952)
Net income	—		—		—		—		12,836		12,836
Balance at September 30, 2020	47,284,336	$	47	$	513,454	$	(7,498)	$	(766,694)	$	(260,691)

						Accumulated
				Additional		Other				Total
	Common Stock			Paid-in		Comprehensive		Accumulated		Stockholders'
	Shares	Amount		Capital		Income (Loss)		Deficit		Equity (Deficit)
Balance at December 31, 2018	46,336,499	$	46	$	471,331	$	(10,928)	$	(609,451)	$	(149,002)
Forfeitures of shares granted to employees	(8,394)		—		—		—		—		—
Equity-based compensation	—		—		14,796		—		—		14,796
Foreign currency translation	—		—		—		(4,748)		—		(4,748)
Issuances of common stock	459,550		1		—		—		—		1
Exercises of options	33,931		—		1,269		—		—		1,269
Dividends paid	—		—		—		—		(82,871)		(82,871)
Net income	—		—		—		—		30,054		30,054
Balance at September 30, 2019	46,821,586	$	47	$	487,396	$	(15,676)	$	(662,268)	$	(190,501)

Schedule of lease cost

	Three Months		Three Months
	Ended		Ended
	September 30, 2020		September 30, 2019
Finance lease cost
Amortization of right-of-use assets	$	6,382	$	4,963
Interest expense on finance lease liabilities		4,804		4,414
Operating lease cost		4,269		3,716
Total lease costs	$	15,455	$	13,093

	Nine Months			Nine Months
	Ended			Ended
	September 30, 2020			September 30, 2019
Finance lease cost
Amortization of right-of-use assets	$	16,117		$	14,851
Interest expense on finance lease liabilities		13,794			13,230
Operating lease cost		12,860			10,497
Total lease costs	$	42,771		$	38,578
Other lease information
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from finance leases	$	(14,150)		$	(12,957)
Operating cash flows from operating leases		(13,785)			(8,443)
Financing cash flows from finance leases		(19,392)			(7,035)
Right-of-use assets obtained in exchange for new finance lease liabilities		61,504			11,342
Right-of-use assets obtained in exchange for new operating lease liabilities		24,866			6,912
Weighted-average remaining lease term — finance leases (in years)		12.3			14.5
Weighted-average remaining lease term — operating leases (in years)		20.4			21.7
Weighted average discount rate — finance leases		10.5	%		10.5	%
Weighted average discount rate — operating leases		5.4	%		5.7	%

Schedule of future minimum payments under finance leases

The future minimum payments (principal and interest) under these finance leases are as follows (in thousands):

For the twelve months ending September 30,
2021	$	33,471
2022		32,638
2023		31,650
2024		31,753
2025		28,495
Thereafter		225,320
Total minimum finance lease obligations		383,327
Less—amounts representing interest		(170,387)
Present value of minimum finance lease obligations		212,940
Current maturities		(15,252)
Finance lease obligations, net of current maturities	$	197,688

Schedule of future minimum payments under operating lease agreements

The future minimum payments under these operating lease agreements are as follows (in thousands):

For the twelve months ending September 30,
2021	$	17,579
2022		16,535
2023		15,674
2024		14,198
2025		12,124
Thereafter		103,809
Total minimum operating lease obligations		179,919
Less—amounts representing interest		(66,466)
Present value of minimum operating lease obligations		113,453
Current maturities		(12,006)
Lease obligations, net of current maturities	$	101,447

Schedule of impact on financial statement line items from adopting ASC 606

			Current-period
	Balance at		Provision for		Write offs		Balance at
	June 30,		Expected Credit		Charged Against		September 30,
Description	2020		Losses		Allowance		2020
Allowance for credit losses (deducted from accounts receivable)
Three months ending September 30, 2020	$	2,115	$	1,174	$	(1,085)	$	2,204

			Current-period
	Balance at		Provision for		Write offs		Balance at
	December 31,		Expected Credit		Charged Against		September 30,
Description	2019		Losses		Allowance		2020
Allowance for credit losses (deducted from accounts receivable)
Nine months ending September 30, 2020	$	1,771	$	3,942	$	(3,509)	$	2,204