Fair value measurements (goodwill and non-recurring asset impairment analyses) (Details) $ in Thousands		3 Months Ended			9 Months Ended
	Jul. 01, 2020 USD ($) reporting_units	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($) reporting_units	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2019 USD ($)
Goodwill impairment and non-recurring fair value measurements [Line Items]
Goodwill impairment charges		$ 0	$ 67,673		$ 67,673
Goodwill		736,779			736,779			$ 804,487
Total impairment charge		2,760		$ 390,980	97,973	$ 390,980
Direct-to-Consumer reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value							$ 35,000
Percentage of fair value in excess of carrying value							26.00%
Reporting units for which quantitative analysis completed [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Number of reporting units | reporting_units	2		2
Reporting units for which quantitative analysis completed [Member] | Minimum [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value							$ 37,000
Percentage of fair value in excess of carrying value							121.00%
Reporting units for which quantitative analysis completed [Member] | Maximum [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value							$ 954,000
Percentage of fair value in excess of carrying value							189.00%
Promotional Solutions reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value	$ 210,000
Percentage of fair value in excess of carrying value	132.00%
Goodwill impairment charges			$ 63,356
Goodwill			62,785
Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Goodwill impairment charges			4,317
Reporting units for which qualitative analysis completed [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Number of reporting units | reporting_units	2
Payments reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value							$ 490,000
Percentage of fair value in excess of carrying value							189.00%
Checks reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value							$ 955,000
Percentage of fair value in excess of carrying value							180.00%
Cloud Data Analytics reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Amount of fair value in excess of carrying value	$ 100,000
Percentage of fair value in excess of carrying value	63.00%
Non-recurring fair value measurement [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Other assets		11,210			11,210
Non-recurring fair value measurement [Member] | Assets held for sale [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Asset impairment charges					7,514
Non-recurring fair value measurement [Member] | Small business distributors [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Estimated fair value, intangibles		$ 4,479			$ 4,479
Non-recurring fair value measurement [Member] | Small business distributors [Member] | Measurement input, revenue growth rate [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Intangibles fair value inputs		0.00%			0.00%
Non-recurring fair value measurement [Member] | Small business distributors [Member] | Measurement input, gross margin growth rate [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Intangibles fair value inputs		1.00%			1.00%
Non-recurring fair value measurement [Member] | Small business distributors [Member] | Measurement input, discount rate [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Intangibles fair value inputs		11.00%			11.00%
Non-recurring fair value measurement [Member] | Amortizable intangibles [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Asset impairment charges			$ 17,678
Non-recurring fair value measurement [Member] | Amortizable intangibles [Member] | Cloud Solutions Web Hosting reporting unit [Member] | Measurement input, revenue growth rate [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Intangibles fair value inputs			(31.00%)
Non-recurring fair value measurement [Member] | Amortizable intangibles [Member] | Cloud Solutions Web Hosting reporting unit [Member] | Measurement input, gross margin growth rate [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Intangibles fair value inputs			(5.20%)
Non-recurring fair value measurement [Member] | Amortizable intangibles [Member] | Cloud Solutions Web Hosting reporting unit [Member] | Measurement input, discount rate [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Intangibles fair value inputs			9.00%
Non-recurring fair value measurement [Member] | Customer lists/relationships [Member] | Small business distributors [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Asset impairment charges		$ 2,356	$ 2,752		$ 5,108
Non-recurring fair value measurement [Member] | Customer lists/relationships [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Asset impairment charges			8,397
Estimated fair value, intangibles			0
Non-recurring fair value measurement [Member] | Internal-use software [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Asset impairment charges			6,932
Estimated fair value, intangibles			2,172
Non-recurring fair value measurement [Member] | Other intangible assets [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Asset impairment charges			2,349
Estimated fair value, intangibles			0
Non-recurring fair value measurement [Member] | Significant unobservable inputs (Level 3) [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Other assets		11,210			11,210
Non-recurring fair value measurement [Member] | Significant unobservable inputs (Level 3) [Member] | Small business distributors [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Estimated fair value, intangibles		$ 4,479			$ 4,479
Non-recurring fair value measurement [Member] | Significant unobservable inputs (Level 3) [Member] | Customer lists/relationships [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Estimated fair value, intangibles			0
Non-recurring fair value measurement [Member] | Significant unobservable inputs (Level 3) [Member] | Internal-use software [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Estimated fair value, intangibles			2,172
Non-recurring fair value measurement [Member] | Significant unobservable inputs (Level 3) [Member] | Other intangible assets [Member] | Cloud Solutions Web Hosting reporting unit [Member]
Goodwill impairment and non-recurring fair value measurements [Line Items]
Estimated fair value, intangibles			$ 0