Summary of Significant Accounting Policies - Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2013
Cash paid during the year for:
Interest	$ 254us-gaap_InterestPaid	$ 289us-gaap_InterestPaid	$ 245us-gaap_InterestPaid
Income taxes	6,215us-gaap_IncomeTaxesPaid	9,112us-gaap_IncomeTaxesPaid	9,770us-gaap_IncomeTaxesPaid
Details of acquisitions:
Fair value of assets acquired	18,128	0	0
Liabilities assumed	204	0	0
Net assets acquired	17,924	0	0
Less cash acquired	2,778us-gaap_CashAcquiredFromAcquisition	0us-gaap_CashAcquiredFromAcquisition	0us-gaap_CashAcquiredFromAcquisition
Net cash paid for acquisitions	$ 15,146	$ 0	$ 0

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The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

+ References

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-Publisher FASB

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The amount of cash paid for interest during the period.

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The net book value of a nonmonetary asset transferred or exchanged in connection with the acquisition of a business or asset in a noncash transaction. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Nonmonetary assets and liabilities are assets and liabilities that will not result in cash receipts or cash payments in the future.

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The value of an asset or business acquired in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The total amount of [all] liabilities that an Entity assumes in acquiring a business or in consideration for an asset received in a noncash (or part noncash) acquisition. Noncash is defined as transactions during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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