Summary of Significant Accounting Policies - Financing Receivables (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Mar. 31, 2016
Credit quality of the Company's financing receivables using Aging Analysis
Total gross sales-type leases	$ 12,400	$ 11,394
Allowance	(164)	(505)
Total net sales-type leases	12,236	10,889
Not Past Due
Credit quality of the Company's financing receivables using Aging Analysis
Lease balances included in consolidated accounts receivable—current	119	294
Lease balances included in consolidated accounts receivable—long-term	13	101
Total gross sales-type leases	132	395
Allowance	0	0
Total net sales-type leases	132	395
1-90 days past due
Credit quality of the Company's financing receivables using Aging Analysis
Lease balances included in consolidated accounts receivable—current	1	4
Lease balances included in consolidated accounts receivable—long-term	0	0
Total gross sales-type leases	1	4
Allowance	0	0
Total net sales-type leases	1	4
Greater than 90 days past due
Credit quality of the Company's financing receivables using Aging Analysis
Lease balances included in consolidated accounts receivable—current	3	10
Lease balances included in consolidated accounts receivable—long-term	0	0
Total gross sales-type leases	3	10
Allowance	0	(9)
Total net sales-type leases	3	1
Total past due
Credit quality of the Company's financing receivables using Aging Analysis
Lease balances included in consolidated accounts receivable—current	4	14
Lease balances included in consolidated accounts receivable—long-term	0	0
Total gross sales-type leases	4	14
Allowance	0	(9)
Total net sales-type leases	4	5
Total sales-type leases
Credit quality of the Company's financing receivables using Aging Analysis
Lease balances included in consolidated accounts receivable—current	123	308
Lease balances included in consolidated accounts receivable—long-term	13	101
Total gross sales-type leases	136	409
Allowance	0	(9)
Total net sales-type leases	$ 136	$ 400

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