Finance Assets (Aging of Receivables) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 1,651,763	$ 1,689,473
1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	1,584,533	1,621,914
Contract value	1,584,533	1,621,914
Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	67,230	67,559
Still accruing interest	10,531	12,545
Not accruing interest	56,699	55,014
Contract value	67,230	67,559
Sales-type lease receivables | North America
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,012,917	1,023,549
Sales-type lease receivables | North America | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	960,922	971,002
Contract value	960,922	971,002
Sales-type lease receivables | North America | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	51,995	52,547
Still accruing interest	8,757	10,807
Not accruing interest	43,238	41,740
Contract value	51,995	52,547
Sales-type lease receivables | International
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	290,618	292,059
Sales-type lease receivables | International | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	284,696	286,170
Contract value	284,696	286,170
Sales-type lease receivables | International | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	5,922	5,889
Still accruing interest	1,774	1,738
Not accruing interest	4,148	4,151
Contract value	5,922	5,889
Loan receivables | North America
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	314,664	339,373
Loan receivables | North America | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	305,623	330,503
Contract value	305,623	330,503
Loan receivables | North America | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	9,041	8,870
Still accruing interest	0	0
Not accruing interest	9,041	8,870
Contract value	9,041	8,870
Loan receivables | International
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	33,564	34,492
Loan receivables | International | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	33,292	34,239
Contract value	33,292	34,239
Loan receivables | International | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	272	253
Still accruing interest	0	0
Not accruing interest	272	253
Contract value	$ 272	$ 253