Summary of Significant Accounting Policies (Narrative) (Details) - Accounting Standards Update 2016-02 [Member] $ in Millions |
Jan. 01, 2019
USD ($)
|
|---|---|
| Assets, Total [Member] | |
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |
| New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | $ 172.0 |
| Liabilities, Total [Member] | |
| New Accounting Pronouncements or Change in Accounting Principle [Line Items] | |
| New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification | $ 172.0 |