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Retirement Plans (Narrative) (Details) $ in Thousands | 9 Months Ended
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Sep. 30, 2019 USD ($) plan
Defined Benefit Plan Disclosure |
Defined contribution plan number | 6
United States |
Defined Benefit Plan Disclosure |
Number of retirement plans | 3
Number of defined benefit plans | 1
Defined contribution plan number | 2
Defined benefit plans, estimated future employer contributions in current fiscal year | $ | $ 550
Canada |
Defined Benefit Plan Disclosure |
Defined contribution plan number | 2
United Kingdom |
Defined Benefit Plan Disclosure |
Defined contribution plan number | 2
Defined benefit plans, estimated future employer contributions in current fiscal year | $ | $ 241
Defined benefit plan, contributions by employer | $ | $ 187

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