Investments and Fair Value Measurements - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Investments And Fair Value Measurements [Line Items]
Available-for-sale securities, net realized losses		$ 100,000	$ 100,000	$ 100,000
Net unrealized gains on sale of securities included in other comprehensive income	100,000		100,000		300,000
Cash equivalents and short term investments	190,414,000		190,414,000		198,153,000
Contingent consideration liability	29,627,000		29,627,000		38,050,000	8,704,000
Acquisition-related executive deferred compensation	200,000	200,000	465,000	456,000	907,000
Contingent liability, current	21,200,000		21,200,000
Contingent liability, noncurrent	8,400,000		8,400,000
Earnout interest accretion			800,000		1,700,000
Probability-adjusted revenue			5.00%
Increase in earnout liability	1,000,000		1,000,000
Decrease in earnout liability	1,400,000		1,400,000
Increase or decrease in fair value contingent consideration	300,000		300,000
Percentage of increase or decrease in the fair value of contingent consideration	1.00%		1.00%
Stop loss deductible			125,000
Self-insurance	1,558,000		1,558,000		1,375,000	1,640,000
Severity of claims experienced or medical cost inflation			10.00%
Increase/Decrease in self-insurance liability			100,000
Notional amount of our derivative assets and liabilities	20,900,000		20,900,000		3,200,000
Designated for cash flow hedge [Member]
Investments And Fair Value Measurements [Line Items]
Notional amount of our derivative assets and liabilities	2,700,000		2,700,000		2,700,000
Alphagraph [Member]
Investments And Fair Value Measurements [Line Items]
Earnout payments			700,000
Entrac, Cretaprint, Streamline, Alphagraph, And Metrics [Member]
Investments And Fair Value Measurements [Line Items]
Fair value of contingent consideration decreased			(1,600,000)
Entrac and Alphagraph [Member]
Investments And Fair Value Measurements [Line Items]
Fair value of contingent consideration decreased					(2,100,000)
Streamline [Member]
Investments And Fair Value Measurements [Line Items]
Earnout payments					600,000
Radius [Member]
Investments And Fair Value Measurements [Line Items]
Contingent consideration liability						2,100,000
Earnout payments			1,000,000		300,000
FX Colors [Member]
Investments And Fair Value Measurements [Line Items]
Contingent consideration liability						190,000
Earnout payments					100,000
Cretaprint [Member]
Investments And Fair Value Measurements [Line Items]
Contingent consideration liability						16,445,000
Earnout payments			8,900,000
Money market funds [Member]
Investments And Fair Value Measurements [Line Items]
Cash equivalents and short term investments	123,502,000		123,502,000		112,714,000
Net Asset Value per share	$ 1.00		$ 1.00		$ 1.00
U.S. Government and sponsored entities [Member]
Investments And Fair Value Measurements [Line Items]
Cash equivalents and short term investments	5,034,000		5,034,000		20,177,000
U.S. Government and sponsored entities [Member] | Cash equivalents [Member]
Investments And Fair Value Measurements [Line Items]
Cash equivalents and short term investments					2,800,000
Corporate debt securities [Member]
Investments And Fair Value Measurements [Line Items]
Cash equivalents and short term investments	41,691,000		41,691,000		42,069,000
Corporate debt securities [Member] | Cash equivalents [Member]
Investments And Fair Value Measurements [Line Items]
Cash equivalents and short term investments	$ 3,400,000		$ 3,400,000		$ 1,700,000
Minimum [Member]
Investments And Fair Value Measurements [Line Items]
Probability of achieving revenue	70.00%		70.00%
Minimum [Member] | Earnout [Member]
Investments And Fair Value Measurements [Line Items]
Fair value discount rate			4.20%
Maximum [Member]
Investments And Fair Value Measurements [Line Items]
Probability of achieving revenue	100.00%		100.00%
Maximum [Member] | Earnout [Member]
Investments And Fair Value Measurements [Line Items]
Fair value discount rate			6.40%