Cash Flow Information - Supplemental Cash Flow Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Elements [Abstract]
Cash required by operating leases	$ 12,026
Finance leases - interest	439
Finance leases - principal	5,555
Operating lease additions	38,225
Finance lease additions	$ 6,412
Capital lease additions		$ 4,400	$ 4,600

Amount of increase in lease obligation from new lease.

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- Definition

Amount of interest paid on finance lease liability.

+ References

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- Definition

Amount of cash outflow for principal payment on finance lease.

+ References

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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