Condensed Consolidated Statement of Changes in Retained Earnings, Accumulated Other Comprehensive Loss and Noncontrolling Interests (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Stockholders' Equity [Abstract]
Tax on pension and post-retirement plan adjustments	$ 1,384	$ 614	$ 2,050	$ 1,682
Preferred stock, dividends (in dollars per share)	$ 0.5625	$ 0.5625	$ 0.5625	$ 0.5625

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Subparagraph (i-k)
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
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-Section 45
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