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Convertible Securities	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Convertible Securities	Convertible Securities As of September 30, 2018, the Company had 5.15% junior convertible trust preferred securities outstanding (the “junior convertible securities”). Effective August 10, 2018 and in accordance with the convertible securities indenture, the Company adjusted the conversion rate of the junior convertible securities from 0.2500 shares of common stock to 0.2525 shares of common stock per $50.00 junior convertible security, equivalent to an adjusted conversion price of $198.02 per share of common stock. The adjustment was the result of the Company’s cumulative declared dividends on its common stock since the initiation of its dividend through August 2018.

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- Definition

Information about convertible debt arrangements, which may include amounts of borrowings, the underlying arrangements, repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, and other matters important to users of the financial statements.

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