4.
Accounts Receivable
Accounts receivable consisted of the following at December 31, 2020 and 2019:
(in thousands) 2020 2019
Accounts receivable - billed S 4365 S 3,091
Less allowance for doubtful accounts (68) (50)
Accounts receivable - billed, net S 4,297 S 3,041
Accounts receivable - unbitled S 4,473 S 2,575
Less allowance for doubtful accounts - -
Accounts receivable - unbilled, net S 4,473 S 2,575
Deferred Charges and Other Assets
2. Property, Plant and Equipment
The components of property, plant and equipment as of December 31, 2020 and 2019 were
Adoption of New Accounting Standards
Contract Assets and Liabilities
As a significant change in one or more of these estimates could affect the profitability of the
Company’s contracts, management reviews and updates the Company's contract-related
estimates regularly through a Company-wide project review process in which management
reviews the progress and execution of the Company's performance obligations and the
estimate at completion. As part of this process, management reviews information including,
but not limited to, any outstanding key contract matters, progress towards completion and
Contributions in Aid of Construction
Under construction contracts with real estate developers and others, the Company’s utility
subsidiaries may receive non-refundable advances for the cost of installing new water mains.
These advances are recorded as CIAC. The Company’s utility subsidiaries also record to plant
and CIAC the fair market value of developer installed mains and any excess of fair market
value over the cost of community water systems purchased from developers. CIAC are
amortized over the life of the related properties.
Accounts Receivable ~ Unbilled, Net
We read our customer meters on a monthly basis and record revenues based on meter
reading results. Information from the last meter reading date is used to estimate the value of
unbilled revenues through the end of the accounting period. Estimates of water utility
revenues for water delivered to customers but not yet billed are accrued at the end of each
accounting period. Actual results could differ from those estimates.
Restricted Cash — Bond Project Funds
Maintenance, repairs and minor improvements are charged to expense as incurred. Improve-
ments which significantly increase the value of property, plant and equipment are capitalized.
Cash and Cash Equivalents
Cash and cash equivalents generally consist of cash, money market funds and other short-
term liquid investments with original maturities of three months or less.
Restricted Cash — RSF
