Marketable Investments (Tables)

12 Months Ended

Dec. 31, 2013

Investments Debt And Equity Securities [Abstract]

Summary of Company's Marketable Investments

The following table summarizes the Company’s marketable investments (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Market Value
December 31, 2013
Available-for-sale securities
State and municipal obligations	$	6,809	$	5	$	—		$	6,814
Federal agency and corporate obligations		74,179		112		(92	)		74,199
Total available-for-sale securities	$	80,988	$	117	$	(92	)	$	81,013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Market Value
December 31, 2012
Available-for-sale securities
State and municipal obligations	$	18,859	$	27	$	(14	)	$	18,872
Federal agency and corporate obligations		115,653		380		(29	)		116,004
Total short-term available-for-sale securities		134,512		407		(43	)		134,876
Auction rate securities (ARS), long-term		11,000		—		(2,030	)		8,970
Total available-for-sale securities	$	145,512	$	407	$	(2,073	)	$	143,846

Summary of Maturity Periods of the Marketable Securities

The following table summarizes the maturity periods of the marketable securities in the Company’s portfolio as of December 31, 2013.

	FY 2014		FY2015		FY2016		Total
Federal agency and corporate obligations	$	24,390	$	28,844	$	20,965	$	74,199
State and municipal obligations		4,763		2,051		—		6,814
Total	$	29,153	$	30,895	$	20,965	$	81,013

Summary of Gross Unrealized Losses and Market Value of Available-for-Sale Securities with Unrealized Losses

The following table shows the gross unrealized losses and market value of Forrester’s available-for-sale securities with unrealized losses that are not deemed to be other-than-temporary, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position (in thousands):

	As of December 31, 2013
	Less Than 12 Months				12 Months or Greater
	Market Value		Unrealized Losses		Market Value		Unrealized Losses
State and municipal bonds	$	—	$	—	$	—	$	—
Federal agency and corporate obligations		30,645		92		—		—
Total	$	30,645	$	92	$	—	$	—

	As of December 31, 2012
	Less Than 12 Months				12 Months or Greater
	Market Value		Unrealized Losses		Market Value		Unrealized Losses
State and municipal bonds	$	9,430	$	14	$	—	$	—
Federal agency and corporate obligations		17,716		29		—		—
ARS		—		—		8,970		2,030
Total	$	27,146	$	43	$	8,970	$	2,030

Summary of Company's Fair Value Hierarchy for its Financial Assets

The following table represents the Company’s fair value hierarchy for its financial assets (cash equivalents and marketable investments) measured at fair value on a recurring basis (in thousands):

	As of December 31, 2013
	Level 1		Level 2		Level 3		Total
Money market funds (1)	$	6,897	$	—	$	—	$	6,897
State and municipal obligations		—		6,814		—		6,814
Federal agency and corporate obligations (2)		—		80,449		—		80,449
Total	$	6,897	$	87,263	$	—	$	94,160
	As of December 31, 2012
	Level 1		Level 2		Level 3		Total
Money market funds (1)	$	815	$	—	$	—	$	815
State and municipal obligations		—		18,872		—		18,872
Federal agency and corporate obligations (2)		—		148,117		—		148,117
ARS		—		—		8,970		8,970
Total	$	815	$	166,989	$	8,970	$	176,774

(1) Included in cash and cash equivalents.

(2) $6.2 million and $32.1 million included in cash and cash equivalents at December 31, 2013 and 2012, respectively, as original maturities at the time of purchase were 90 days or less.

Summary of Changes in Fair Value of Level 3 Financial Assets

The following table provides a summary of changes in fair value of the Company’s Level 3 financial assets for the years ended December 31, 2013 and 2012 (in thousands):

	ARS
Balance at December 31, 2011	$	9,565
Sales		—
Losses included in other comprehensive income		(595	)
Balance at December 31, 2012		8,970
Sales		(9,108	)
Gains included in other comprehensive income		138
Losses transferred out of other comprehensive loss		1,892
Losses included in earnings		(1,892	)
Balance at December 31, 2013	$	—