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v3.19.1

Retirement plans - Asset allocation (Details) | Dec. 31, 2018 | Dec. 31, 2017
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Employee Benefits [Abstract] |  |
Equity securities | 20.00% | 46.00%
Debt securities | 57.00% | 29.00%
Cash and other short-term securities | 23.00% | 25.00%
Total | 100.00% | 100.00%

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- Definition Cash And Cash Equivalents, Amount Contributed To Fair Value Of Plan Assets, Allocation Percentage + References No definition available. + Details
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