Basis of Presentation	3 Months Ended
Mar. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation	1. Basis of Presentation The financial statements included in this report reflect all normal and recurring adjustments which, in the opinion of management, are necessary for a fair presentation of our consolidated financial position at March 31, 2020 and December 31, 2019, the consolidated results of operations for the three months ended March 31, 2020 and 2019, and consolidated cash flows for the three months ended March 31, 2020 and 2019. The unaudited results of operations for the interim periods reported are not necessarily indicative of results to be expected for the full year. The financial statements were prepared in accordance with the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain notes or other financial information that are normally required by generally accepted accounting principles (GAAP) in the United States have been condensed or omitted from these interim financial statements. These statements, therefore, should be read in conjunction with the consolidated financial statements and related notes included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2019. In the first quarter of 2020, we adopted Accounting Standards Update (ASU) 2016-13, Financial Instruments – Credit Losses. This ASU makes changes to the impairment model for trade receivables, net investments in leases, debt securities, loans and certain other instruments. The standard requires the use of a forward-looking "expected loss" model compared with the prior "incurred loss" model. We calculate expected credit losses for our receivables using the probability of default and the expected loss given default. Historical data, current market conditions, and forecasts of future economic conditions are used to determine the probability of default and the expected loss given default. The adoption of this ASU did not have a material impact to our financial statements.

Basis of Presentation

3 Months Ended

Mar. 31, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

1. Basis of Presentation

The financial statements included in this report reflect all normal and recurring adjustments which, in the opinion of management, are necessary for a fair presentation of our consolidated financial position at March 31, 2020 and December 31, 2019, the consolidated results of operations for the three months ended March 31, 2020 and 2019, and consolidated cash flows for the three months ended March 31, 2020 and 2019. The unaudited results of operations for the interim periods reported are not necessarily indicative of results to be expected for the full year.

The financial statements were prepared in accordance with the requirements of the Securities and Exchange Commission (SEC) for interim reporting. As permitted under those rules, certain notes or other financial information that are normally required by generally accepted accounting principles (GAAP) in the United States have been condensed or omitted from these interim financial statements. These statements, therefore, should be read in conjunction with the consolidated financial statements and related notes included in the Corporation’s Annual Report on Form 10-K for the year ended December 31, 2019.

In the first quarter of 2020, we adopted Accounting Standards Update (ASU) 2016-13, Financial Instruments – Credit Losses. This ASU makes changes to the impairment model for trade receivables, net investments in leases, debt securities, loans and certain other instruments. The standard requires the use of a forward-looking "expected loss" model compared with the prior "incurred loss" model. We calculate expected credit losses for our receivables using the probability of default and the expected loss given default. Historical data, current market conditions, and forecasts of future economic conditions are used to determine the probability of default and the expected loss given default. The adoption of this ASU did not have a material impact to our financial statements.