Accumulated Other Comprehensive Income (Tables)

3 Months Ended

Apr. 01, 2018

Changes in Accumulated Other Comprehensive Income

Changes in accumulated other comprehensive income, which are presented net of tax, consist of the following:

	For the Three Months Ended April 1, 2018
	Foreign Currency Translation Adjustment		Unrealized Gains (Losses) on Marketable Securities			Retirement Plans Prior Service Credit			Total
	(in thousands)
Three Months Ended April 1, 2018
Balance at December 31, 2017, net of tax of $0, $1,815,  $(932), respectively	$	15,919	$	1,362		$	1,495		$	18,776
Other comprehensive income (loss) before reclassifications, net of tax of $0, $(718), $0, respectively		10,541		(2,687	)		—			7,854
Amounts reclassified from accumulated other comprehensive income, net of tax of $0, $78, $(18), respectively		—		1,668			(61	)		1,607
Net current period other comprehensive income (loss), net of tax of $0, $(640), $(18), respectively		10,541		(1,019	)		(61	)		9,461
Reclassification of income tax effects from the Tax Reform Act, net of tax of $0, $(691), $(78), respectively (a)		—		691			78			769
Reclassification of unrealized gains on equity securities, net of tax of $0, $(902), $0, respectively (b)		—		(3,125	)		—			(3,125	)
Balance at April 1, 2018, net of tax of $0, $(418), $(1,028), respectively	$	26,460	$	(2,091	)	$	1,512		$	25,881

(a) In the three months ended April 1, 2018, Teradyne early adopted the ASU 2018-02, “Income Statement—Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income.” As a result, the stranded tax effects resulting from the Tax Reform Act enacted in December 2017 was reclassified from accumulated other comprehensive income to retained earnings.

(b) In the three months ended April 1, 2018, Teradyne adopted the ASU 2016-01, “Financial Instruments—Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities.” See Note B: “Accounting Policies.”

	For the Three Months ended April 2, 2017
	Foreign Currency Translation Adjustments			Unrealized Gains (Losses) on Marketable Securities			Retirement Plans Prior Service Credit			Total
	(in thousands)
Three Months Ended April 2, 2017
Balance at December 31, 2016, net of tax of $0, $209, $(778), respectively	$	(21,921	)	$	(60	)	$	1,767		$	(20,214	)
Other comprehensive income before reclassifications, net of tax of $0, $420,$0, respectively		8,963			513			—			9,476
Amounts reclassified from accumulated other comprehensive income, net of tax of $0, $(64), $(38), respectively		—			(95	)		(68	)		(163	)
Net current period other comprehensive income (loss), net of tax of $0, $356, $(38), respectively		8,963			418			(68	)		9,313
Balance as April 2, 2017, net of tax of $0, $565, $(816), respectively	$	(12,958	)	$	358		$	1,699		$	(10,901	)

Reclassifications Out of Accumulated Other Comprehensive Income (Loss) to Statements of Operations

Reclassifications out of accumulated other comprehensive income (loss) to the statement of operations for the three months ended April 1, 2018 and April 2, 2017 were as follows:

Details about Accumulated Other Comprehensive (Loss) Income Components	For the Three Months Ended					Affected Line Item in the Statements of Operations
	April 1, 2018			April 2, 2017
	(in thousands)
Available-for-sale marketable securities:
Unrealized (losses) gains, net of tax of $(78), $64, respectively	$	(1,668	)	$	95	Interest (expense) income
Defined benefit pension and postretirement plans:
Amortization of prior service credit, net of tax of $18, $38, respectively		61			68	(a)
Total reclassifications, net of tax of $(60), $102, respectively	$	(1,607	)	$	163	Net income

(a) The amortization of prior service credit is included in the computation of net periodic pension cost and postretirement benefit; see Note P: “Retirement Plans.”