Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2013

Accounting Policies [Abstract]

Schedule of Liabilities Measured at Fair Value on a Recurring Basis [Table Text Block]

Financial liabilities measured at fair value on a recurring basis consisted of the following, as of:

	Fair value measurement using
(in thousands)	Level 1		Level 2		Level 3		Total
Fair value as of December 31, 2013
Financial Liabilities:
Derivative instruments(1)	—		427		—		427
Total financial liabilities	$	—	$	427	$	—	$	427
Fair value as of December 31, 2012
Financial liabilities:
Derivative instruments(1)	—		1,296		—		1,296
Total financial liabilities	$	—	$	1,296	$	—	$	1,296

(1) The fair value of our interest rate swaps was based on model-driven valuations using LIBOR rates, which are observable at commonly quoted intervals. Accordingly, our interest rate swaps are classified within Level 2 of the fair value hierarchy.

Schedule of Finite-lived Intangible Assets, Estimated Useful Life [Table Text Block]

We amortize finite-lived intangible assets over their estimated useful lives as follows.

	Basis of amortization	Amortization period (in years)
Customer relationships	Straight-line and accelerated (1)	4-15
Marketing assets	Straight-line	1-8
Acquired software and technology	Straight-line	1-10
Non-compete agreements	Straight-line	1-5
Database	Straight-line	8

(1) Certain of the customer relationships are amortized on an accelerated basis.

Schedule of Changes in Allowance for Sales Returns and Doubtful Accounts [Table Text Block]

Below is a summary of the changes in our allowance for sales returns.

Years ended December 31, (in thousands)	Balance at beginning of year		Provision/adjustment		Write-off			Balance at end of year
2013	$	7,730	$	4,132	$	(6,704	)	$	5,158
2012	3,652		8,914		(4,836		)	7,730
2011	2,263		5,619		(4,230		)	3,652

Below is a summary of the changes in our allowance for doubtful accounts.

Years ended December 31, (in thousands)	Balance at beginning of year		Provision/adjustment		Write-off			Balance at end of year
2013	$	816	$	775	$	(1,136	)	$	455
2012	261		976		(421		)	816
2011	424		27		(190		)	261

Schedule of Changes in Deferred Sales Commission Costs [Table Text Block]

Below is a summary of the changes in our deferred sales commission costs included in prepaid expenses and other current assets.

Years ended December 31, (in thousands)	Balance at beginning of year		Additions		Expense			Balance at end of year
2013	$	18,142	$	20,487	$	(18,541	)	$	20,088
2012	16,452		19,693		(18,003		)	18,142
2011	11,548		18,415		(13,511		)	16,452

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

The following table sets forth the computation of basic and diluted earnings per share:

	Year ended December 31,
(in thousands, except share and per share amounts)	2013		2012		2011
Numerator:
Net income	$	30,472	$	6,583	$	33,220
Denominator:
Weighted average common shares	44,684,812		44,145,535		43,522,563
Add effect of dilutive securities:
Employee stock-based compensation	736,328		546,310		626,491
Weighted average common shares assuming dilution	45,421,140		44,691,845		44,149,054
Earnings per share:
Basic	$	0.68	$	0.15	$	0.76
Diluted	$	0.67	$	0.15	$	0.75

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

The following shares underlying stock-based awards were not included in diluted earnings per share because their inclusion would have been anti-dilutive:

	Year ended December 31,
	2013	2012	2011
Shares excluded from calculations of diluted EPS	116,438	434,050	422,418