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Basis of Presentation (Details) $ in Thousands | Mar. 31, 2019 USD ($) lease | Jan. 01, 2019 USD ($) lease | Jan. 01, 2018
--- | --- | --- | ---
Schedule of Equity Method Investments [Line Items] |  |  |
Lease Liabilities | $ 1,235 |  |
Operating lease, liabilities | 40,225 |  |
Financing lease, right-of-use assets | 1,213 |  |
Operating lease, right-of-use assets | $ 35,686 |  |
Number of operating lease agreements | lease | 42 |  |
ASU No. 2016-02 |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Lease Liabilities |  | $ 1,200 |
Operating lease, liabilities |  | 33,700 |
Financing lease, right-of-use assets |  | 1,200 |
Operating lease, right-of-use assets |  | $ 33,400 |
Number of operating lease agreements | lease |  | 1 |
New Partnership |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Equity method investment, ownership percentage |  |  | 30.00%
S&T Evergreen Insurance LLC | Subsidiaries |  |  |
Schedule of Equity Method Investments [Line Items] |  |  |
Percentage of ownership in subsidiary sold |  |  | 70.00%

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