Reduction in cash due to no longer including the former subsidiary's cash in the consolidated entity's cash.

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Changes in Operations United Kingdom - ERS (Details) $ in Thousands, € in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2018 EUR (€)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 EUR (€)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)
Proceeds from divestiture of business	€ 11.2	$ 13,100
Proceeds from sale of business, net of cash				€ 6.8	$ 7,927	$ 0
Cash of divested business that transferred to buyer				€ 4.4	5,200
Loss on sale of business					$ 1,400
ERS Railways [Member] \| U.K. Europe Operations [Member]
Restructuring Charges			$ 1,300			$ 4,500