Acquisitions (Details) $ in Thousands, NZD in Millions, AUD in Millions	1 Months Ended					3 Months Ended			12 Months Ended
	Apr. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Oct. 31, 2015 USD ($)	Oct. 31, 2015 AUD	Sep. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Mar. 31, 2014 USD ($)	Mar. 31, 2014 NZD	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Jan. 31, 2016 USD ($)	Jan. 31, 2016 NZD	Dec. 31, 2015 NZD
Business Acquisition [Line Items]
Acquisitions									$ 226,907	$ 119,589
Mandatorily redeemable noncontrolling interests		$ 18,981							0	18,981
Goodwill		1,881,547				$ 1,780,758			2,107,255	1,881,547	$ 1,780,758
Depreciation and amortization									172,578	150,377	143,364
Business Combination, Acquisition Related Costs									6,900	3,900	9,000
FNC, Inc. [Member]
Business Acquisition [Line Items]
Amount paid to acquire business	$ 400,000
Business Combination, Contingent Consideration, Liability	8,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent	89,700
PIQ Acquisition [Member]
Business Acquisition [Line Items]
Remaining equity interest acquired												40.00%	40.00%
Mandatorily redeemable noncontrolling interests		19,000								19,000		$ 19,000	NZD 27.8	NZD 27.8
RELS LLC [Member]
Business Acquisition [Line Items]
Amount paid to acquire business		65,000
Property and equipment		27,000								27,000
Gain on investments and other, net		34,300
Business Acquisition, Goodwill, Expected Tax Deductible Amount		$ 11,500								$ 11,500
Cordell Information Pty Ltd [Member]
Business Acquisition [Line Items]
Amount paid to acquire business			$ 49,100	AUD 70.0
Property and equipment			$ 14,300
Landsafe [Member]
Business Acquisition [Line Items]
Amount paid to acquire business					$ 122,000
BofA's credit services [Member]
Business Acquisition [Line Items]
Amount paid to acquire business						$ 19,600
MSB/Data Quick [Member]
Business Acquisition [Line Items]
Amount paid to acquire business							$ 652,500
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual											67,500
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual											5,800
Depreciation and amortization											18,600
Terralink [Member]
Business Acquisition [Line Items]
Amount paid to acquire business							11,900	NZD 14.5
Property and equipment							$ 2,100
Property, Plant and Equipment [Member] | FNC, Inc. [Member]
Business Acquisition [Line Items]
Property and equipment	$ 79,800
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	12 years
Property, Plant and Equipment [Member] | RELS LLC [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
Property, Plant and Equipment [Member] | Cordell Information Pty Ltd [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			10 years	10 years
Property, Plant and Equipment [Member] | BofA's credit services [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life										3 years
Property, Plant and Equipment [Member] | Terralink [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life							5 years	5 years
Client lists | FNC, Inc. [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	16 years
Finite-lived Intangible Assets Acquired	$ 141,800
Client lists | RELS LLC [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
Finite-lived Intangible Assets Acquired		$ 48,400
Client lists | Cordell Information Pty Ltd [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			8 years	8 years
Finite-lived Intangible Assets Acquired			$ 5,500
Client lists | Landsafe [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life					10 years
Finite-lived Intangible Assets Acquired					$ 53,400
Client lists | BofA's credit services [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life						10 years
Finite-lived Intangible Assets Acquired						$ 6,100
Client lists | Terralink [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life							15 years	15 years
Finite-lived Intangible Assets Acquired							$ 1,400
Non-compete agreements | FNC, Inc. [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	5 years
Finite-lived Intangible Assets Acquired	$ 18,800
Other Intangible Assets [Member] | FNC, Inc. [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	10 years
Finite-lived Intangible Assets Acquired	$ 2,900
Other Intangible Assets [Member] | RELS LLC [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
Finite-lived Intangible Assets Acquired		$ 5,000
Other Intangible Assets [Member] | Landsafe [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life					10 years
Finite-lived Intangible Assets Acquired					$ 4,300
Trade Names [Member] | FNC, Inc. [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	19 years
Finite-lived Intangible Assets Acquired	$ 15,900
Trade Names [Member] | Cordell Information Pty Ltd [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life			4 years	4 years
Finite-lived Intangible Assets Acquired			$ 600
Trade Names [Member] | Terralink [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life							12 years	12 years
Finite-lived Intangible Assets Acquired							$ 200
Capitalized Data [Member] | Terralink [Member]
Business Acquisition [Line Items]
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life							15 years	15 years
Finite-lived Intangible Assets Acquired							$ 6,000
Risk Management and Work Flow [Member]
Business Acquisition [Line Items]
Acquisitions									0	$ 0
Goodwill		918,467				823,429			918,467	918,467	823,429
Risk Management and Work Flow [Member] | BofA's credit services [Member]
Business Acquisition [Line Items]
Property and equipment						4,300					4,300
Acquisitions						9,200
Property Intelligence [Member]
Business Acquisition [Line Items]
Acquisitions									226,907	119,589
Goodwill		963,080				$ 957,329			1,188,788	$ 963,080	$ 957,329
Property Intelligence [Member] | FNC, Inc. [Member]
Business Acquisition [Line Items]
Acquisitions	225,700								225,700
Goodwill, Purchase Accounting Adjustments									$ 14,200
Property Intelligence [Member] | RELS LLC [Member]
Business Acquisition [Line Items]
Acquisitions		$ 23,100
Property Intelligence [Member] | Cordell Information Pty Ltd [Member]
Business Acquisition [Line Items]
Acquisitions			$ 31,900
Property Intelligence [Member] | Landsafe [Member]
Business Acquisition [Line Items]
Acquisitions					$ 64,600
Property Intelligence [Member] | MSB/Data Quick [Member]
Business Acquisition [Line Items]
Property and equipment							177,311
Goodwill							307,773
Business Acquisition, Goodwill, Expected Tax Deductible Amount							167,800
Property Intelligence [Member] | Terralink [Member]
Business Acquisition [Line Items]
Acquisitions							$ 2,300
RELS LLC [Member]
Business Acquisition [Line Items]
Remaining equity interest acquired		49.90%								49.90%				49.90%
Ownership percentage in equity method investment		50.10%								50.10%				50.10%
Maximum [Member] | FNC, Inc. [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred	475,000
Other Payments to Acquire Businesses	$ 75,000