Revenue (Disaggregates of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue from leasing transactions and financing									$ 3,554,075	$ 3,205,125	$ 3,211,522
Revenue	$ 1,028,417	$ 891,898	$ 837,492	$ 796,268	$ 831,343	$ 790,125	$ 788,573	$ 795,084	3,554,075	3,205,125	3,211,522
ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									2,898,540	2,484,837	2,425,862
Products/services transferred at a point in time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									293,648	334,046	386,844
Products/services transferred over time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									2,604,892	2,150,791	2,039,018
Business services
Disaggregation of Revenue [Line Items]
Revenue from products and services									2,191,306	1,710,801	1,566,470
Revenue from leasing transactions and financing									0	0	0
Revenue									2,191,306	1,710,801	1,566,470
Support services
Disaggregation of Revenue [Line Items]
Revenue from products and services									473,292	506,187	552,472
Revenue from leasing transactions and financing									0	0	0
Revenue									473,292	506,187	552,472
Financing
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									341,034	368,090	394,557
Revenue									341,034	368,090	394,557
Equipment sales
Disaggregation of Revenue [Line Items]
Revenue from products and services									74,660	80,562	88,616
Revenue from leasing transactions and financing									240,222	271,542	307,036
Revenue									314,882	352,104	395,652
Supplies
Disaggregation of Revenue [Line Items]
Revenue from products and services									159,282	187,287	218,304
Revenue from leasing transactions and financing									0	0	0
Revenue									159,282	187,287	218,304
Rentals
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									74,279	80,656	84,067
Revenue									74,279	80,656	84,067
Sales And Services
Disaggregation of Revenue [Line Items]
Revenue from products and services									2,898,540	2,484,837	2,425,862
Revenue from leasing transactions and financing									655,535	720,288	785,660
Revenue									3,554,075	3,205,125	3,211,522
Global Ecommerce
Disaggregation of Revenue [Line Items]
Revenue from leasing transactions and financing									1,618,897	1,151,510	1,022,862
Global Ecommerce | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									1,618,897	1,151,510	1,022,862
Global Ecommerce | Products/services transferred at a point in time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Global Ecommerce | Products/services transferred over time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									1,618,897	1,151,510	1,022,862
Global Ecommerce | Business services
Disaggregation of Revenue [Line Items]
Revenue from products and services									1,618,897	1,151,510	1,022,862
Global Ecommerce | Support services
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Global Ecommerce | Financing
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									0	0	0
Global Ecommerce | Equipment sales
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									0	0	0
Global Ecommerce | Supplies
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Global Ecommerce | Rentals
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									0	0	0
Global Ecommerce | Sales And Services
Disaggregation of Revenue [Line Items]
Revenue from products and services									1,618,897	1,151,510	1,022,862
Presort Services
Disaggregation of Revenue [Line Items]
Revenue from leasing transactions and financing									521,212	529,588	515,795
Presort Services | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									521,212	529,588	515,795
Presort Services | Products/services transferred at a point in time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Presort Services | Products/services transferred over time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									521,212	529,588	515,795
Presort Services | Business services
Disaggregation of Revenue [Line Items]
Revenue from products and services									521,212	529,588	515,795
Presort Services | Support services
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Presort Services | Financing
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									0	0	0
Presort Services | Equipment sales
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									0	0	0
Presort Services | Supplies
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Presort Services | Rentals
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									0	0	0
Presort Services | Sales And Services
Disaggregation of Revenue [Line Items]
Revenue from products and services									521,212	529,588	515,795
SendTech Solutions
Disaggregation of Revenue [Line Items]
Revenue from leasing transactions and financing									1,413,966	1,524,027	1,672,865
SendTech Solutions | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									758,431	803,739	887,205
SendTech Solutions | Products/services transferred at a point in time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									293,648	334,046	386,844
SendTech Solutions | Products/services transferred over time | ASC 606
Disaggregation of Revenue [Line Items]
Revenue from products and services									464,783	469,693	500,361
SendTech Solutions | Business services
Disaggregation of Revenue [Line Items]
Revenue from products and services									51,197	29,703	27,813
SendTech Solutions | Support services
Disaggregation of Revenue [Line Items]
Revenue from products and services									473,292	506,187	552,472
SendTech Solutions | Financing
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									341,034	368,090	394,557
SendTech Solutions | Equipment sales
Disaggregation of Revenue [Line Items]
Revenue from products and services									74,660	80,562	88,616
Revenue from leasing transactions and financing									240,222	271,542	307,036
SendTech Solutions | Supplies
Disaggregation of Revenue [Line Items]
Revenue from products and services									159,282	187,287	218,304
SendTech Solutions | Rentals
Disaggregation of Revenue [Line Items]
Revenue from products and services									0	0	0
Revenue from leasing transactions and financing									74,279	80,656	84,067
SendTech Solutions | Sales And Services
Disaggregation of Revenue [Line Items]
Revenue from products and services									$ 758,431	$ 803,739	$ 887,205