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Income Taxes (Earliest Tax Year) (Detail) | 12 Months Ended
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Dec. 31, 2020
Pennsylvania |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2012
Connecticut |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2017
Virginia |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2017
West Virginia |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2017
New York |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2015
Utah |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2017
South Carolina |
Operation In Major Geographical Areas Tax Year [Line Items] |
Earliest Open Tax Year | 2013

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