Fair Value Measurements - Financial Instruments Required to be Carried at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Liabilities
Contingent consideration	$ (6,257)	$ (6,198)
Foreign currency exchange contracts
Assets
Foreign currency exchange contracts	837
Liabilities
Foreign currency exchange contracts	(38)	(237)
Interest rate cap contracts
Assets
Interest rate cap contracts	451	2,023
Interest rate swap agreements
Liabilities
Interest rate swap agreements	(6,967)	(4,881)
Level 1
Liabilities
Contingent consideration	0	0
Level 1 \| Foreign currency exchange contracts
Assets
Foreign currency exchange contracts	0
Liabilities
Foreign currency exchange contracts	0	0
Level 1 \| Interest rate cap contracts
Assets
Interest rate cap contracts	0	0
Level 1 \| Interest rate swap agreements
Liabilities
Interest rate swap agreements	0	0
Level 2
Liabilities
Contingent consideration	0	0
Level 2 \| Foreign currency exchange contracts
Assets
Foreign currency exchange contracts	837
Liabilities
Foreign currency exchange contracts	(38)	(237)
Level 2 \| Interest rate cap contracts
Assets
Interest rate cap contracts	451	2,023
Level 2 \| Interest rate swap agreements
Liabilities
Interest rate swap agreements	(6,967)	(4,881)
Level 3
Liabilities
Contingent consideration	(6,257)	(6,198)
Level 3 \| Foreign currency exchange contracts
Assets
Foreign currency exchange contracts	0
Liabilities
Foreign currency exchange contracts	0	0
Level 3 \| Interest rate cap contracts
Assets
Interest rate cap contracts	0	0
Level 3 \| Interest rate swap agreements
Liabilities
Interest rate swap agreements	$ 0	$ 0

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
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-Publisher FASB
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-Publisher FASB
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-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

+ References

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