Fair Value Measurements and Derivative Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

Financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. Our assessment of the significance of a particular input to the fair value measurement requires judgment and may affect their placement within the fair value hierarchy. The following tables show, by level within the fair value hierarchy, our financial assets and liabilities that are accounted for at fair value on a recurring basis at December 31, 2017 and 2016.

	December 31, 2017
	Level 1		Level 2			Level 3		Total
Assets:
Investment securities
Money market funds / commercial paper	$	143,349	$	542,568		$	—	$	685,917
Equity securities	—		40,717			—		40,717
Commingled fixed income securities	1,569		4,516			—		6,085
Government and related securities	116,041		18,587			—		134,628
Corporate debt securities	—		75,109			—		75,109
Mortgage-backed / asset-backed securities	—		158,202			—		158,202
Derivatives
Interest rate swap	—		1,776			—		1,776
Foreign exchange contracts	—		122			—		122
Total assets	$	260,959	$	841,597		$	—	$	1,102,556
Liabilities:
Derivatives
Foreign exchange contracts	$	—	$	(335	)	$	—	$	(335	)
Total liabilities	$	—	$	(335	)	$	—	$	(335	)

	December 31, 2016
	Level 1		Level 2			Level 3		Total
Assets:
Investment securities
Money market funds / commercial paper	$	114,471	$	217,175		$	—	$	331,646
Equity securities	—		24,571			—		24,571
Commingled fixed income securities	1,536		22,132			—		23,668
Government and related securities	116,822		19,358			—		136,180
Corporate debt securities	—		69,891			—		69,891
Mortgage-backed / asset-backed securities	—		158,996			—		158,996
Derivatives
Interest rate swap	—		1,588			—		1,588
Foreign exchange contracts	—		637			—		637
Total assets	$	232,829	$	514,348		$	—	$	747,177
Liabilities:
Derivatives
Foreign exchange contracts	$	—	$	(3,717	)	$	—	$	(3,717	)
Total liabilities	$	—	$	(3,717	)	$	—	$	(3,717	)

Available-for-sale Securities

At December 31, 2017 and 2016, available-for-sale securities consisted of the following:

	December 31, 2017
	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
Government and related securities	$	131,872	$	1,984	$	(1,090	)	$	132,766
Corporate debt securities	73,612		1,724		(227		)	75,109
Commingled fixed income securities	1,796		—		(40		)	1,756
Mortgage-backed / asset-backed securities	158,496		1,348		(1,642		)	158,202
Total	$	365,776	$	5,056	$	(2,999	)	$	367,833

	December 31, 2016
	Amortized cost		Gross unrealized gains		Gross unrealized losses			Estimated fair value
Government and related securities	$	136,316	$	1,571	$	(1,707	)	$	136,180
Corporate debt securities	69,376		1,180		(665		)	69,891
Commingled fixed income securities	1,568		—		(32		)	1,536
Mortgage-backed / asset-backed securities	159,312		1,566		(1,882		)	158,996
Total	$	366,572	$	4,317	$	(4,286	)	$	366,603

Schedule of Available-for-sale Securities Reconciliation

At December 31, 2017, scheduled maturities of available-for-sale securities were as follows:

	Amortized cost		Estimated fair value
Within 1 year	$	38,624	$	38,414
After 1 year through 5 years	111,756		111,704
After 5 years through 10 years	68,599		69,154
After 10 years	146,797		148,561
Total	$	365,776	$	367,833

Schedule of Derivative Instruments in Statement of Financial Position, Fair Value

The fair value of our derivative instruments at December 31, 2017 and 2016 was as follows:

		December 31,
Designation of Derivatives	Balance Sheet Location	2017			2016
Derivatives designated as hedging instruments
Foreign exchange contracts	Other current assets and prepayments	$	57		$	487
	Accounts payable and accrued liabilities	(144		)	(136		)
Interest rate swap	Other non-current assets	1,776			1,588
Derivatives not designated as hedging instruments
Foreign exchange contracts	Other current assets and prepayments	65			150
	Accounts payable and accrued liabilities	(191		)	(3,581		)
	Total derivative assets	1,898			2,225
	Total derivative liabilities	(335		)	(3,717		)
	Total net derivative liability	$	1,563		$	(1,492	)

Schedule of Cash Flow Hedging Instruments, Statements of Financial Performance and Financial Position, Location

The following represents the results of cash flow hedging relationships for the years ended December 31, 2017 and 2016:

	Years Ended December 31,
	Derivative Gain (Loss) Recognized in AOCI (Effective Portion)					Location of Gain (Loss) (Effective Portion)	Gain (Loss) Reclassified from AOCI to Earnings (Effective Portion)
Derivative Instrument	2017			2016			2017			2016
Foreign exchange contracts	$	(650	)	$	496	Revenue	$	(179	)	$	(68	)
						Cost of sales	(32		)	222
Interest rate swap	$	1,776		$	1,588	Interest Expense	—			—
							$	(211	)	$	154

Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location

The following represents the results of our non-designated derivative instruments for the years ended December 31, 2017 and 2016:

		Years Ended December 31,
		Derivative Gain (Loss) Recognized in Earnings
Derivatives Instrument	Location of Derivative Gain (Loss)	2017			2016
Foreign exchange contracts	Selling, general and administrative expense	$	(2,203	)	$	(2,382	)

Fair Value, by Balance Sheet Grouping

The carrying value and estimated fair value of our debt at December 31, 2017 and 2016 was as follows:

	December 31,
	2017		2016
Carrying value	$	3,830,335	$	3,364,890
Fair value	$	3,718,986	$	3,412,581