Equity and Noncontrolling Interest (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Beginning Balance	$ 1,320,914,000	$ 1,242,366,000
Net income (loss)	38,632,000	(28,344,000)
Amounts reported in other comprehensive income (loss)	(26,632,000)	(43,486,000)
Dividends, Common Stock	(7,062,000)	(6,834,000)
Distributions to noncontrolling affiliate shareholders		(751,000)
Acquisition of noncontrolling interest		1,047,000
Share based compensation plans	3,601,000	1,039,000
Ending Balance	1,329,453,000	1,162,541,000
Cummulative effect of accounting change [Member]
Beginning Balance	(402,000)
Adjusted balance [Member]
Beginning Balance	1,241,964,000
Common Stock [Member]
Beginning Balance	17,851,000	17,735,000
Net income (loss)	0	0
Amounts reported in other comprehensive income (loss)	0	0
Dividends, Common Stock	0	0
Distributions to noncontrolling affiliate shareholders		0
Acquisition of noncontrolling interest		0
Share based compensation plans	24,000	17,000
Ending Balance	17,875,000	17,752,000
Common Stock [Member] | Cummulative effect of accounting change [Member]
Beginning Balance	0
Common Stock [Member] | Adjusted balance [Member]
Beginning Balance	17,735,000
Additional Paid-in Capital [Member]
Beginning Balance	905,171,000	888,218,000
Net income (loss)	0	0
Amounts reported in other comprehensive income (loss)	0	0
Dividends, Common Stock	0	0
Distributions to noncontrolling affiliate shareholders		0
Acquisition of noncontrolling interest		707,000
Share based compensation plans	3,577,000	1,022,000
Ending Balance	908,748,000	888,533,000
Additional Paid-in Capital [Member] | Cummulative effect of accounting change [Member]
Beginning Balance	0
Additional Paid-in Capital [Member] | Adjusted balance [Member]
Beginning Balance	888,218,000
Retained Earnings [Member]
Beginning Balance	423,940,000	412,979,000
Net income (loss)	38,615,000	(28,381,000)
Amounts reported in other comprehensive income (loss)	0	0
Dividends, Common Stock	(7,062,000)	(6,834,000)
Distributions to noncontrolling affiliate shareholders		0
Acquisition of noncontrolling interest		0
Share based compensation plans	0	0
Ending Balance	455,493,000	377,362,000
Retained Earnings [Member] | Cummulative effect of accounting change [Member]
Beginning Balance	(402,000)
Retained Earnings [Member] | Adjusted balance [Member]
Beginning Balance	412,577,000
Accumulated Other Comprehensive Income (Loss) [Member]
Beginning Balance	(26,598,000)	(78,170,000)
Net income (loss)	0	0
Amounts reported in other comprehensive income (loss)	(26,630,000)	(43,354,000)
Dividends, Common Stock	0	0
Distributions to noncontrolling affiliate shareholders		0
Acquisition of noncontrolling interest		0
Share based compensation plans	0	0
Ending Balance	(53,228,000)	(121,524,000)
Accumulated Other Comprehensive Income (Loss) [Member] | Cummulative effect of accounting change [Member]
Beginning Balance	0
Accumulated Other Comprehensive Income (Loss) [Member] | Adjusted balance [Member]
Beginning Balance	(78,170,000)
Noncontrolling Interest [Member]
Beginning Balance	550,000	1,604,000
Net income (loss)	17,000	37,000
Amounts reported in other comprehensive income (loss)	(2,000)	(132,000)
Dividends, Common Stock	0	0
Distributions to noncontrolling affiliate shareholders		(751,000)
Acquisition of noncontrolling interest		340,000
Share based compensation plans	0	0
Ending Balance	565,000	$ 418,000
Noncontrolling Interest [Member] | Cummulative effect of accounting change [Member]
Beginning Balance	0
Noncontrolling Interest [Member] | Adjusted balance [Member]
Beginning Balance	$ 1,604,000