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Receivables (Tables) | 9 Months Ended
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Sep. 30, 2017
Receivables [Line Items] |
Maximum And Average Outstanding Cash Proceeds | IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016
Maximum outstanding aggregate cash proceeds |  | $112.0 |  |  |  | $172.0 |  |  |  | $112.0 |  |  |  | $172.0 |
Average outstanding aggregate cash proceeds | 66.2 |  |  | 112.3 |  |  | 58.7 |  |  | 91.5 |
Receivables Sold Under The Receivables Agreement | The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
| September 30, 2017 |  | December 31, 2016
Customer accounts receivable |  | $153.6 |  |  |  | $157.6 |
Unbilled utility revenues | 89.1 |  |  | 90.4 |
Other receivables | 1.1 |  |  | 0.1 |
Receivables sold to third party | 243.8 |  |  | 248.1 |
Less: cash proceeds (a) | 112.0 |  |  | 21.0 |
Deferred proceeds | 131.8 |  |  | 227.1 |
Less: allowance for doubtful accounts | 16.5 |  |  | 16.0 |
Fair value of deferred proceeds |  | $115.3 |  |  |  | $211.1 |
(a) | Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements.
Additional Attributes Of Receivables Sold Under The Receivables Agreement | Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016
Collections reinvested in receivables |  | $347.9 |  |  |  | $499.7 |  |  |  | $1,283.2 |  |  |  | $1,362.1 |
Write-off losses (recoveries), net | 3.5 |  |  | (0.3 | ) |  | 10.4 |  |  | (0.6 | )
IPL [Member] |
Receivables [Line Items] |
Maximum And Average Outstanding Cash Proceeds | IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016
Maximum outstanding aggregate cash proceeds |  | $112.0 |  |  |  | $172.0 |  |  |  | $112.0 |  |  |  | $172.0 |
Average outstanding aggregate cash proceeds | 66.2 |  |  | 112.3 |  |  | 58.7 |  |  | 91.5 |
Receivables Sold Under The Receivables Agreement | The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):
| September 30, 2017 |  | December 31, 2016
Customer accounts receivable |  | $153.6 |  |  |  | $157.6 |
Unbilled utility revenues | 89.1 |  |  | 90.4 |
Other receivables | 1.1 |  |  | 0.1 |
Receivables sold to third party | 243.8 |  |  | 248.1 |
Less: cash proceeds (a) | 112.0 |  |  | 21.0 |
Deferred proceeds | 131.8 |  |  | 227.1 |
Less: allowance for doubtful accounts | 16.5 |  |  | 16.0 |
Fair value of deferred proceeds |  | $115.3 |  |  |  | $211.1 |
(a) | Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements.
Additional Attributes Of Receivables Sold Under The Receivables Agreement | Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and nine months ended September 30 were as follows (in millions):
| Three Months |  | Nine Months
| 2017 |  | 2016 |  | 2017 |  | 2016
Collections reinvested in receivables |  | $347.9 |  |  |  | $499.7 |  |  |  | $1,283.2 |  |  |  | $1,362.1 |
Write-off losses (recoveries), net | 3.5 |  |  | (0.3 | ) |  | 10.4 |  |  | (0.6 | )

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