Condensed Consolidated Unaudited Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities:
Net income	$ 31,300us-gaap_ProfitLoss	$ 24,403us-gaap_ProfitLoss
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Depreciation and amortization	4,621	4,434
Share-based compensation	2,831us-gaap_ShareBasedCompensation	2,488us-gaap_ShareBasedCompensation
Non-cash contribution to 401(k) plan	1,963wso_NonCashContributionTo401KPlan	1,759wso_NonCashContributionTo401KPlan
Provision for doubtful accounts	1,288us-gaap_ProvisionForDoubtfulAccounts	927us-gaap_ProvisionForDoubtfulAccounts
Excess tax benefits from share-based compensation	(358)	(131)
Other, net	758us-gaap_OtherNoncashIncomeExpense	961us-gaap_OtherNoncashIncomeExpense
Changes in operating assets and liabilities:
Accounts receivable	(6,884)	1,992
Inventories	(126,900)us-gaap_IncreaseDecreaseInInventories	(126,316)us-gaap_IncreaseDecreaseInInventories
Accounts payable and other liabilities	72,050	112,346
Other, net	2,548	2,038
Net cash (used in) provided by operating activities	(16,783)	24,901
Cash flows from investing activities:
Capital expenditures	(3,114)	(1,736)
Proceeds from sale of property and equipment	71	70
Net cash used in investing activities	(3,043)	(1,666)
Cash flows from financing activities:
Net proceeds (repayments) under revolving credit agreement	38,497	(2,553)
Net proceeds from issuances of common stock	1,381	873
Excess tax benefits from share-based compensation	358	131
Net repayments of other long-term obligations	(41)	(26)
Distributions to noncontrolling interest	(3,654)	(7,614)
Dividends on Common and Class B common stock	(24,524)us-gaap_PaymentsOfDividendsCommonStock	(13,923)us-gaap_PaymentsOfDividendsCommonStock
Net cash provided by (used in) financing activities	12,017	(23,112)
Effect of foreign exchange rate changes on cash and cash equivalents	(387)	(144)
Net decrease in cash and cash equivalents	(8,196)	(21)
Cash and cash equivalents at beginning of period	24,447	19,478
Cash and cash equivalents at end of period	$ 16,251	$ 19,457

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.