CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 12,502us-gaap_NetIncomeLoss	$ 13,446us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	487us-gaap_Depreciation	697us-gaap_Depreciation
Share based compensation	1,118us-gaap_ShareBasedCompensation	1,105us-gaap_ShareBasedCompensation
Discontinued project costs	1,714pets_DiscontinuedProjectCharge
Deferred income taxes	129us-gaap_DeferredIncomeTaxExpenseBenefit	(84)us-gaap_DeferredIncomeTaxExpenseBenefit
Bad debt expense	66us-gaap_ProvisionForDoubtfulAccounts	75us-gaap_ProvisionForDoubtfulAccounts
(Increase) decrease in operating assets and increase (decrease) in liabilities:
Accounts receivable	343	(286)
Inventories - finished goods	14,114	7,060
Prepaid income taxes	54us-gaap_IncreaseDecreaseInPrepaidTaxes	(165)us-gaap_IncreaseDecreaseInPrepaidTaxes
Prepaid expenses and other current assets	763	(1,449)
Accounts payable	(1,892)	(2,411)
Income taxes payable	283	(162)
Accrued expenses and other current liabilities	(153)	(152)
Net cash provided by operating activities	29,528	17,674
Cash flows from investing activities:
Net change in short term investments	(53)	(62)
Purchases of property and equipment	(398)	(39)
Net cash used in investing activities	(451)	(101)
Cash flows from financing activities:
Dividends paid	(10,353)us-gaap_PaymentsOfDividendsCommonStock	(9,914)us-gaap_PaymentsOfDividendsCommonStock
Tax adjustment related to restricted stock	39	123
Net cash used in financing activities	(10,314)	(9,791)
Net increase in cash and cash equivalents	18,763	7,782
Cash and cash equivalents, at beginning of period	18,305	18,155
Cash and cash equivalents, at end of period	37,068	25,937
Supplemental disclosure of cash flow information:
Cash paid for income taxes	6,929us-gaap_IncomeTaxesPaid	7,776us-gaap_IncomeTaxesPaid
Dividends payable in accrued expenses	$ 225us-gaap_LiabilitiesAssumed1	$ 241us-gaap_LiabilitiesAssumed1

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