Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Supplemental Cash Flow Information [Abstract]
Interest paid	$ 16,180	$ 16,711
Noncash investing and financing activity
Dividends declared not yet paid	5,748	5,527
Capital projects incurred but not yet paid	$ 8,459	$ 15,974

Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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