Finance Assets (Aging of Receivables) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	$ 1,602,776	$ 1,689,473
1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	1,547,837	1,621,914
Contract value	1,547,837	1,621,914
Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	54,939	67,559
Still accruing interest	8,068	12,545
Not accruing interest	46,871	55,014
Contract value	54,939	67,559
Sales-type lease receivables | North America
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	1,000,825	1,023,549
Sales-type lease receivables | North America | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	959,594	971,002
Contract value	959,594	971,002
Sales-type lease receivables | North America | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	41,231	52,547
Still accruing interest	6,350	10,807
Not accruing interest	34,881	41,740
Contract value	41,231	52,547
Sales-type lease receivables | International
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	268,733	292,059
Sales-type lease receivables | International | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	262,464	286,170
Contract value	262,464	286,170
Sales-type lease receivables | International | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	6,269	5,889
Still accruing interest	1,718	1,738
Not accruing interest	4,551	4,151
Contract value	6,269	5,889
Loan receivables | North America
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	301,575	339,373
Loan receivables | North America | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	294,349	330,503
Contract value	294,349	330,503
Loan receivables | North America | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	7,226	8,870
Still accruing interest	0	0
Not accruing interest	7,226	8,870
Contract value	7,226	8,870
Loan receivables | International
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	31,643	34,492
Loan receivables | International | 1 - 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	31,430	34,239
Contract value	31,430	34,239
Loan receivables | International | Greater than 90 days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Financing receivables	213	253
Still accruing interest	0	0
Not accruing interest	213	253
Contract value	$ 213	$ 253