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Financial Instruments with Off-Balance Sheet Risk | 3 Months Ended
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Mar. 31, 2020
Financial Instruments with Off-Balance Sheet Risk [Abstract] |
Financial Instruments with Off-Balance Sheet Risk | Financial Instruments with Off-Balance Sheet Risk The Company is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its clients. These financial instruments include commitments to extend credit and standby letters of credit. Commitments to extend credit are agreements to lend to a client as long as there is no violation of any condition established in the commitment contract. Since many of the commitments are expected to expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. Standby letters of credit are conditional commitments issued by the Company to guarantee the performance of a client to a third party. The following table presents our financial instruments with off-balance sheet risk, as well as the activity in the allowance for off-balance sheet credit losses related to those financial instruments:
|  | Three Months Ended March 31,
|  | 2020 |  | 2019
Beginning balance, prior to adoption of ASC 326 |  | $ | — |  |  | $ | — |
Impact of adopting ASC 326 |  | 2.3 |  |  | — |
Provision for credit loss expense |  | (0.2 | ) |  | — |
Ending balance of allowance for off-balance sheet credit losses |  | $ | 2.1 |  |  | $ | — |
|  | March 31, 2020 |  | December 31, 2019
Unused credit card lines* |  | $ | 1,480.5 |  |  | $ | 1,450.5 |
Commitments to extend credit* |  | 2,122.4 |  |  | 2,067.0 |
Standby letter of credit |  | 56.2 |  |  | 42.7 |
* In conjunction with the adoption of ASC 326, the Company presented the December 31, 2019 balances to conform to the March 31, 2020 presentation.

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