The following table presents revenue by service offering for the three months ended March 31, 2020:

(1)Includes wholesale and colocation lease revenue of $5.4 million.

The following table presents revenue by service offering for the three months ended March 31, 2019:


	Three months ended March 31, 2019
	Residential		Business		Total
	Subscription		Subscription		Revenue
	(in millions)
HSD	$	108.1	$	19.4	$	127.5
Video		107.4		3.6		111.0
Telephony		16.0		10.7		26.7
Total subscription services revenue	$	231.5	$	33.7	$	265.2
Other business services revenue(1)		—		—		7.1
Other revenue		—		—		14.9
Total revenue	$	231.5	$	33.7	$	287.2

(1)Includes wholesale and colocation lease revenue of $5.5 million.

Costs of Obtaining Contracts with Customers

The following table summarizes the activity of costs of obtaining contracts with customers:


	2020		2019
	(in millions)
Balance at January 1	$	40.7	$	26.3
Deferral		5.7		4.8
Amortization		(2.7)		(1.5)
Balance at March 31	$	43.7	$	29.6

The following table presents current and non-current portion of costs of obtaining contracts with customers as of the end of the corresponding periods:


	March 31, 2020		December 31, 2019
	(in millions)
Current costs of obtaining contracts with customers	$	11.2	$	10.0
Non-current costs of obtaining contracts with customers		32.5		30.7
Total costs of obtaining contracts with customers	$	43.7	$	40.7

The current portion and the non-current portion of costs of obtaining contracts with customers are included in prepaid expenses and other and other non-current assets, respectively, in the Company’s unaudited condensed consolidated balance sheets. Amortization of costs of obtaining contracts with customers is included in selling, general and administrative expense in the Company’s unaudited condensed consolidated statements of operations.

Contract Liabilities

The following table summarizes the activity of current and non-current contract liabilities:


	2020		2019
	(in millions)
Balance at January 1	$	4.2	$	3.9
Deferral		3.7		3.9
Revenue recognized		(4.0)		(3.8)
Balance at March 31	$	3.9	$	4.0

The following table presents current and non-current portion of contract liabilities as of the end of the corresponding periods:


	March 31, 2020		December 31, 2019
	(in millions)
Current contract liabilities	$	3.3	$	3.6
Non-current contract liabilities		0.6		0.6
Total contract liabilities	$	3.9	$	4.2

The current portion and the non-current portion of contract liabilities are included in the current portion of unearned service revenue and other non-current liabilities, respectively, in the Company’s unaudited condensed consolidated balance sheets.

Unsatisfied Performance Obligations

Revenue from month-to-month residential subscription service contracts have historically represented a significant portion of the Company’s revenue and the Company expects that this will continue to be the case in future periods. All residential subscription service performance obligations will be satisfied within one year.

A summary of expected commercial revenue to be recognized in future periods related to performance obligations which have not been satisfied or are partially unsatisfied as of March 31, 2020 is set forth in the table below:


	2020		2021		2022		Thereafter		Total
	(in millions)
Subscription services	$	58.9	$	50.2	$	20.9	$	8.1	$	138.1
Other business services		3.1		2.8		1.3		0.5		7.7
Total expected revenue	$	62.0	$	53.0	$	22.2	$	8.6	$	145.8

Provision for Doubtful Accounts

The provision for doubtful accounts and the allowance for doubtful accounts are based on the aging of the individual receivables, historical trends and current and anticipated future economic conditions. The Company manages credit risk by disconnecting services to customers who are delinquent, generally after sixty days of delinquency. The Company has temporarily suspended certain collection activities as a result of participation in the Federal Communications Commission (“FCC”) Keep Americans Connected Pledge effective March 12, 2020. The individual receivables are written-off after all reasonable efforts to collect the funds have been made. Actual write-offs may differ from the amounts reserved.

The following table presents the change in the allowance for doubtful accounts for trade accounts receivable for the three months ended March 31, 2020 compared to the three months ended March 31, 2019:


	2020		2019
	(in millions)
Balance at beginning of period	$	7.5	$	7.5
Provision charged to expense		5.3		3.5
Accounts written off, net of recoveries		(3.8)		(4.0)
Balance at end of period	$	9.0	$	7.0

The Company established an allowance for doubtful accounts for non-trade accounts receivable of $2.0 million for the three months ended March 31, 2020 that is presented within accounts receivable—other in the Company’s unaudited condensed consolidated balance sheets.