Condensed Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 50,831	$ 32,970
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	14,874	16,815
Unrealized foreign currency gain, net	(1,057)	(1,744)
Share-based compensation	6,015	3,945
Other non-cash items	3,229	(2,872)
Changes in operating assets and liabilities:
Accounts receivable, net of allowances	(73,845)	(53,086)
Inventories	(6,506)	(4,743)
Prepaid expenses and other assets	(1,089)	12,567
Accounts payable, accrued expenses and other liabilities	48,409	35,528
Cash provided by operating activities	40,861	39,380
Cash flows from investing activities:
Purchases of property, equipment, and software	(3,246)	(12,231)
Proceeds from disposal of property and equipment	34	1,506
Cash used in investing activities	(3,212)	(10,725)
Cash flows from financing activities:
Proceeds from bank borrowings	0	5,500
Repayments of bank borrowings and capital lease obligations	(669)	(7,565)
Dividends—Series A preferred stock	(6,000)	(6,000)
Repurchases of common stock	(25,946)	(10,000)
Other	(208)	(240)
Cash used in financing activities	(32,823)	(18,305)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(6,183)	(717)
Net change in cash, cash equivalents, and restricted cash	(1,357)	9,633
Cash, cash equivalents, and restricted cash—beginning of period	177,055	152,646
Cash, cash equivalents, and restricted cash—end of period	$ 175,698	$ 162,279