Consolidated Statements of Comprehensive (Loss)/Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income		$ 14,462	$ 20,378	$ 37,620	$ 37,166
Other comprehensive (loss)/income:
Unrealized (loss)/gain on effective cash flow hedges, net of taxes ($3,573), $1,536, ($4,373) and $3,580, respectively		(8,656)	707	(12,870)	7,692
Foreign currency translation (loss)/gain		(18,219)	2,200	(26,030)	13,843
Reclassification adjustments
Gain on cash flow hedges, net of taxes ($426), ($607), ($1,202) and ($891), respectively(1)	[1]	(1,041)	(1,376)	(2,936)	(2,022)
Retirement benefits, net of taxes ($3), $40, ($2) and $47, respectively(2)	[2]	(35)	31	(75)	93
Total other comprehensive (loss)/income		(27,951)	1,562	(41,911)	19,606
Total comprehensive (loss)/income		$ (13,489)	$ 21,940	$ (4,291)	$ 56,772

[1] These are reclassified to net income and are included either in cost of revenues, or operating expenses, as applicable in the unaudited consolidated statements of income. Refer to Note 17 to the unaudited consolidated financial statements.

[2] These are reclassified to net income and are included in other income, net in the unaudited consolidated statements of income. Refer to Note 20 to the unaudited consolidated financial statements.