Business Combinations (Details) (USD $)	3 Months Ended	12 Months Ended	1 Months Ended
	Aug. 31, 2013	Nov. 30, 2013	Dec. 31, 2014	Nov. 30, 2014	Nov. 30, 2012
Business Acquisition [Line Items]
Equity consideration transferred, number of shares	1,334,477
Equity consideration transferred, value	$ 131,500,000
Revenue of acquiree since acquisition date		165,900,000
Net income of acquiree since acquisition date		14,400,000
Nonrecurring adjustment excluded from pro forma income		26,400,000
Current assets		103,600,000		6,574,000	16,442,000
Property and equipment		35,070,000		345,000	4,411,000
Intangible assets		704,346,000		88,465,000	116,534,000
Goodwill		1,105,674,000		130,267,000	230,765,000
Other long-term assets		11,242,000		31,000	1,054,000
Total assets		1,959,932,000		225,682,000	369,206,000
Current liabilities		83,458,000		632,000	8,271,000
Deferred taxes		248,092,000			29,292,000
Deferred revenue				14,322,000	25,164,000
Other long-term liabilities		9,862,000		333,000	211,000
Total liabilities		341,412,000		15,287,000	62,938,000
Purchase price		1,618,520,000		210,395,000	306,268,000
R.L. Polk [Member]
Business Acquisition [Line Items]
Cash consideration transferred, net of cash acquired	1,250,000,000
Current assets		87,076,000
Property and equipment		32,311,000
Intangible assets		620,700,000
Goodwill		935,450,000
Other long-term assets		11,032,000
Total assets		1,686,569,000
Current liabilities		53,785,000
Deferred taxes		243,842,000
Other long-term liabilities		8,926,000
Total liabilities		306,553,000
Purchase price		1,380,016,000
Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Current assets		16,524,000			11,702,000
Property and equipment		2,759,000			2,531,000
Intangible assets		83,646,000			72,034,000
Goodwill		170,224,000			115,987,000
Other long-term assets		210,000			282,000
Total assets		273,363,000			202,536,000
Current liabilities		29,673,000			8,191,000
Deferred taxes		4,250,000			11,631,000
Deferred revenue					12,926,000
Other long-term liabilities		936,000			0
Total liabilities		34,859,000			32,748,000
Purchase price		238,504,000			169,788,000
GlobalSpec Acquisition [Member]
Business Acquisition [Line Items]
Current assets					4,740,000
Property and equipment					1,880,000
Intangible assets					44,500,000
Goodwill					114,778,000
Other long-term assets					772,000
Total assets					166,670,000
Current liabilities					80,000
Deferred taxes					17,661,000
Deferred revenue					12,238,000
Other long-term liabilities					211,000
Total liabilities					30,190,000
Purchase price					136,480,000
Subsequent Event [Member] | Series of Individually Immaterial Business Acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred			$ 123,000,000