Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Accounting for Derivative Instruments and Hedging Activities - Narrative (Details)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	May 15, 2018 USD ($)	May 11, 2018 USD ($)	Jan. 01, 2015 USD ($)	Nov. 28, 2014 EUR (€)	Nov. 28, 2014 USD ($)	Jul. 25, 2014 EUR (€)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Unrealized loss	$ 34,362,000	$ 19,628,000
Designated as Hedging Instrument \| Cash Flow Hedge \| Euro Interest Rate Cap, Start Date 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount \| €						€ 375,000,000.0
Derivative amount of hedged item \| €								€ 399,000,000.0
Designated as Hedging Instrument \| Cash Flow Hedge \| USD Interest Rate Cap, Start Date 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount							$ 350,000,000.0
Derivative amount of hedged item \| €								€ 358,000,000.0
Designated as Hedging Instrument \| Cash Flow Hedge \| Cross Currency Interest Rate Contract
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount			$ 235,000,000.0	$ 235,000,000.0
Designated as Hedging Instrument \| Cash Flow Hedge \| Three Month EURIBOR \| Euro Interest Rate Cap, Start Date 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate								1.00%
Designated as Hedging Instrument \| Cash Flow Hedge \| Three Month USD LIBOR \| USD Interest Rate Cap, Start Date 2014
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Interest rate								2.50%
Designated as Hedging Instrument \| Net Investment Hedging \| Currency Swap
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Notional amount					$ 180,000,000.0
Unrealized loss	$ 2,200,000