Consolidated financial statements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2021
Asset impairment charges	$ 0	$ (4,883)			$ 0	$ (98,989)
Operating income (loss)	26,369	24,315			62,375	(40,275)
Income (loss) before income taxes	18,968	19,952			52,483	(47,165)
Income tax provision	(6,839)	(5,074)			(16,030)	(1,652)
Net income (loss)	12,129	14,878			36,453	(48,817)
Net income (loss) attributable to Deluxe	12,100	14,859			36,391	(48,836)
Total comprehensive loss	14,124	19,053			40,057	(56,649)
Comprehensive loss attributable to Deluxe	$ 14,095	$ 19,034			$ 39,995	$ (56,668)
Basic earnings (loss) per share	$ 0.29	$ 0.36			$ 0.86	$ (1.17)	$ 0.12	$ (5.20)
Diluted earnings (loss) per share	$ 0.28	$ 0.35			$ 0.85	$ (1.18)	$ 0.11	$ (5.20)
ASSETS
Deferred income taxes	$ 3,387				$ 3,387		$ 6,642
Goodwill	1,439,303				1,439,303		702,958
Assets	3,017,476				3,017,476		1,842,175
LIABILITIES AND SHAREHOLDERS' EQUITY
Deferred income taxes	64,723				64,723		5,401
Retained earnings	505,753				505,753		495,153
Total shareholders' equity	552,271	$ 457,892	$ 446,521		552,271	$ 457,892	513,392	$ 546,979	$ 531,373
Total liabilities and shareholders' equity	3,017,476				3,017,476		$ 1,842,175
Cash flows from operating activities:
Net loss	12,129	14,878			36,453	(48,817)
Asset impairment charges	$ 0	$ 4,883			0	98,989
Deferred income taxes					$ 10,977	(11,098)
As previously reported [Member]
Asset impairment charges						(95,213)
Operating income (loss)						(36,499)
Income (loss) before income taxes						(43,389)
Income tax provision						(1,864)
Net income (loss)						(45,253)
Net income (loss) attributable to Deluxe						(45,272)
Total comprehensive loss						(53,085)
Comprehensive loss attributable to Deluxe						$ (53,104)
Basic earnings (loss) per share						$ (1.08)	$ 0.21	$ (4.65)
Diluted earnings (loss) per share						$ (1.10)	$ 0.19	$ (4.65)
ASSETS
Deferred income taxes							$ 5,444
Goodwill							736,844
Assets							1,874,863
LIABILITIES AND SHAREHOLDERS' EQUITY
Deferred income taxes							10,643
Retained earnings							522,599
Total shareholders' equity							540,838
Total liabilities and shareholders' equity							1,874,863
Cash flows from operating activities:
Net loss						$ (45,253)
Asset impairment charges						95,213
Deferred income taxes						(10,886)
Adjustment [Member]
Asset impairment charges			(3,776)	$ (30,110)		(3,776)
Operating income (loss)						(3,776)
Income (loss) before income taxes						(3,776)
Income tax provision			212	6,228		212
Net income (loss)			(3,564)	(23,882)		(3,564)		$ (23,882)
Net income (loss) attributable to Deluxe						(3,564)	(3,564)
Total comprehensive loss						(3,564)
Comprehensive loss attributable to Deluxe						$ (3,564)
Basic earnings (loss) per share						$ (0.09)
Diluted earnings (loss) per share						$ (0.08)
ASSETS
Deferred income taxes							1,198
Goodwill							(33,886)
Assets							(32,688)
LIABILITIES AND SHAREHOLDERS' EQUITY
Deferred income taxes							(5,242)
Retained earnings							(27,446)
Total shareholders' equity							(27,446)
Total liabilities and shareholders' equity							$ (32,688)
Cash flows from operating activities:
Net loss			(3,564)	(23,882)		$ (3,564)		$ (23,882)
Asset impairment charges			$ 3,776	$ 30,110		3,776
Deferred income taxes						$ (212)