Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	[1]	Sep. 27, 2013
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 307,365,845		$ 307,365,845
Amortization expense	5,600,000	$ 5,700,000
Amortization expense, 2019	22,000,000
Amortization expense, 2020	22,000,000
Amortization expense, 2021	22,000,000
Amortization expense, 2022	21,000,000
Amortization expense, 2023	$ 19,000,000
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Finite-Lived Intangible Assets [Line Items]
Goodwill					$ 307,400,000

[1] The condensed consolidated balance sheet at December 31, 2018 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements.