WNS (WNS) 20-F 16 May 18 2018 FY Annual report (foreign) Financial data

Document and Entity Information

Document and Entity Information	12 Months Ended
	Mar. 31, 2018shares
Document - Document and Entity Information [Abstract]
Document Type	20-F
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Trading Symbol	WNS
Entity Registrant Name	WNS (HOLDINGS) LTD
Entity Central Index Key	1,356,570
Current Fiscal Year End Date	--03-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	50,434,080

Consolidated Statements of Fina

Consolidated Statements of Financial Position - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current assets:
Cash and cash equivalents	$ 99,829	$ 69,803
Investments	120,960	111,992
Trade receivables, net	71,388	60,423
Unbilled revenue	61,721	48,915
Funds held for clients	10,066	9,135
Derivative assets	11,738	35,401
Prepayments and other current assets	24,847	27,385
Total current assets	400,549	363,054
Non-current assets:
Goodwill	135,186	134,008
Intangible assets	89,652	96,624
Property and equipment	60,606	54,796
Derivative assets	3,245	6,581
Deferred tax assets	27,395	16,687
Investments	542	429
Other non-current assets	42,388	31,944
Total non-current assets	359,014	341,069
TOTAL ASSETS	759,563	704,123
Current liabilities:
Trade payables	19,703	14,239
Provisions and accrued expenses	28,826	27,217
Derivative liabilities	6,466	3,947
Pension and other employee obligations	64,617	52,933
Current portion of long term debt	27,740	27,613
Deferred revenue	2,908	5,478
Current taxes payable	1,262	1,322
Other liabilities	15,739	16,015
Total current liabilities	167,261	148,764
Non-current liabilities:
Derivative liabilities	2,289	836
Pension and other employee obligations	9,621	10,680
Long term debt	61,391	89,130
Deferred revenue	571	378
Other non-current liabilities	11,662	18,469
Deferred tax liabilities	11,812	20,800
Total non-current liabilities	97,346	140,293
TOTAL LIABILITIES	264,607	289,057
Shareholders' equity:
Share capital (ordinary shares $0.16 (10 pence) par value, authorized 60,000,000 shares; issued: 54,834,080 shares and 53,312,559 shares each as at March 31, 2018 and March 31, 2017, respectively)	8,533	8,333
Share premium	371,764	338,284
Retained earnings	364,424	277,988
Other components of equity	(115,534)	(114,854)
Total shareholder's equity, including shares held in treasury	629,187	509,751
Less: 4,400,000 shares as at March 31, 2018 and 3,300,000 shares as at March 31, 2017, held in treasury, at cost	(134,231)	(94,685)
Total shareholders' equity	494,956	415,066
TOTAL LIABILITIES AND EQUITY	$ 759,563	$ 704,123

Consolidated Statements of Fin3

Consolidated Statements of Financial Position (Parenthetical)	Mar. 31, 2018£ / sharesshares	Mar. 31, 2018$ / sharesshares	Mar. 31, 2017£ / sharesshares	Mar. 31, 2017$ / sharesshares
Statement of financial position [abstract]
Share capital, par value | (per share)	£ 0.10	$ 0.16	£ 0.10	$ 0.16
Share capital, authorized	60,000,000	60,000,000	60,000,000	60,000,000
Share capital, issued	54,834,080	54,834,080	53,312,559	53,312,559
Shares held in treasury, shares	4,400,000	4,400,000	3,300,000	3,300,000

Consolidated Statements of Inco

Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Profit or loss [abstract]
Revenue	$ 757,956	$ 602,546	$ 562,179
Cost of revenue	503,130	403,324	365,360
Gross profit	254,826	199,222	196,819
Operating expenses:
Selling and marketing expenses	41,767	32,631	30,844
General and administrative expenses	117,626	91,742	78,902
Foreign exchange gain, net	(14,973)	(14,514)	(10,969)
Impairment of goodwill	0	21,673
Amortization of intangible assets	15,505	20,539	25,198
Operating profit	94,901	47,151	72,844
Other income, net	(11,230)	(8,689)	(8,494)
Finance expense	4,264	547	278
Profit before income taxes	101,867	55,293	81,060
Provision for income taxes	15,431	17,530	21,180
Profit	$ 86,436	$ 37,763	$ 59,880
Earnings per share of ordinary share
Basic	$ 1.72	$ 0.75	$ 1.17
Diluted	$ 1.63	$ 0.71	$ 1.12

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Statement of comprehensive income [abstract]
Profit	$ 86,436	$ 37,763	$ 59,880
Other comprehensive income/(loss), net of taxes - Items that will not be reclassified to profit or loss:
Pension adjustment	2,486	(1,804)	(130)
Other comprehensive income/(loss), net of taxes - Items that will be reclassified subsequently to profit or loss:
Current period (loss) /gain	(341)	43,118	446
Reclassification to profit/(loss)	(26,436)	(24,777)	(14,222)
Foreign currency translation	14,202	(7,810)	(20,828)
Income tax (provision)/benefit relating to above	9,409	(6,921)	4,259
Other comprehensive income/(loss), net of taxes - Items that will be reclassified subsequently to profit or loss	(3,166)	3,610	(30,345)
Total other comprehensive income/(loss), net of taxes	(680)	1,806	(30,475)
Total comprehensive income	$ 85,756	$ 39,569	$ 29,405

Consolidated Statements of Chan

Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Share capital [member]	Share premium [member]	Retained earnings [member]	Other components of equity: Foreign currency translation reserve [member]	Other components of equity: Cash flow hedging reserve [member]	Other components of equity: Pension adjustments [member]	Treasury shares [member]
Beginning balance at Mar. 31, 2015	$ 389,106	$ 8,141	$ 286,805	$ 180,345	$ (103,529)	$ 15,445	$ 1,899
Beginning balance at Mar. 31, 2015		51,950,662
Shares issued for exercised options and RSUs (Refer note 22)	1,303	$ 70	1,233
Shares issued for exercised options and RSUs (Refer note 22), shares		455,642
Purchase of treasury shares (Refer note 18)	(30,461)							$ (30,461)
Purchase of treasury shares (Refer note 18), shares								1,100,000
Share-based compensation expense (Refer note 22)	17,919		17,919
Excess tax benefits relating to share-based options and RSUs (Refer note 23)	917		917
Transactions with owners	(10,322)	$ 70	20,069					$ (30,461)
Transactions with owners, shares		455,642						1,100,000
Profit	59,880			59,880
Other comprehensive income/(loss), net of taxes	(30,475)				(20,828)	(9,517)	(130)
Total comprehensive income/(loss) for the year	29,405			59,880	(20,828)	(9,517)	(130)
Ending balance at Mar. 31, 2016	408,189	$ 8,211	306,874	240,225	(124,357)	5,928	1,769	$ (30,461)
Ending balance at Mar. 31, 2016		52,406,304						1,100,000
Shares issued for exercised options and RSUs (Refer note 22)	8,941	$ 122	8,819
Shares issued for exercised options and RSUs (Refer note 22), shares		906,255
Purchase of treasury shares (Refer note 18)	(64,224)							$ (64,224)
Purchase of treasury shares (Refer note 18), shares								2,200,000
Share-based compensation expense (Refer note 22)	23,036		23,036
Excess tax benefits relating to share-based options and RSUs (Refer note 23)	(445)		(445)
Transactions with owners	(32,692)	$ 122	31,410					$ (64,224)
Transactions with owners, shares		906,255						2,200,000
Profit	37,763			37,763
Other comprehensive income/(loss), net of taxes	1,806				(7,810)	11,420	(1,804)
Total comprehensive income/(loss) for the year	39,569			37,763	(7,810)	11,420	(1,804)
Ending balance at Mar. 31, 2017	415,066	$ 8,333	338,284	277,988	(132,167)	17,348	(35)	$ (94,685)
Ending balance at Mar. 31, 2017		53,312,559						3,300,000
Shares issued for exercised options and RSUs (Refer note 22)	1,347	$ 200	1,147
Shares issued for exercised options and RSUs (Refer note 22), shares		1,521,521
Purchase of treasury shares (Refer note 18)	(39,546)							$ (39,546)
Purchase of treasury shares (Refer note 18), shares								1,100,000
Share-based compensation expense (Refer note 22)	30,565		30,565
Purchase of equity from non-controlling interest	(52)		(52)
Excess tax benefits relating to share-based options and RSUs (Refer note 23)	1,820		1,820
Transactions with owners	(5,866)	$ 200	33,480					$ (39,546)
Transactions with owners, shares		1,521,521						1,100,000
Profit	86,436			86,436
Other comprehensive income/(loss), net of taxes	(680)				14,202	(17,368)	2,486
Total comprehensive income/(loss) for the year	85,756			86,436	14,202	(17,368)	2,486
Ending balance at Mar. 31, 2018	$ 494,956	$ 8,533	$ 371,764	$ 364,424	$ (117,965)	$ (20)	$ 2,451	$ (134,231)
Ending balance at Mar. 31, 2018		54,834,080						4,400,000

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Profit	$ 86,436	$ 37,763	$ 59,880
Adjustments to reconcile profit to net cash generated from operating activities:
Depreciation and amortization	35,459	37,442	40,633
Impairment of goodwill		21,673
Share-based compensation expense	30,565	23,036	17,919
Amortization of debt issue cost	488	52	13
Allowance for doubtful trade receivables	(499)	(1,040)	(774)
Unrealized exchange loss/(gain), net	2,663	(11,123)	3,997
Current tax expense	24,494	25,785	19,615
Interest expense	3,778	495	265
Interest income	(3,693)	(2,083)	(1,197)
Dividend income	(3,570)	(4,131)	(5,039)
Unrealized gain on investments	(3)	(6)	(41)
Income from funds held in escrow	(239)	(280)
Reversal of contingent consideration in relation to acquisition	(1,324)
Loss/ (gain) on sale of property and equipment	(325)	143	(100)
Deferred income taxes	(9,063)	(8,255)	1,565
Deferred rent	1,289	1,136	631
Excess tax benefit from share-based compensation expense	(685)	(270)	(229)
Unrealized gain on derivative instruments	5,283	(1,930)	(1,219)
Others, net		23	98
Changes in operating assets and liabilities:
Trade receivables and unbilled revenue	(16,413)	(1,630)	(5,725)
Other assets	(4,196)	(2,137)	(9,162)
Trade payables	2,029	(4,203)	(2,290)
Deferred revenue	(2,560)	2,303	(1,050)
Other liabilities	13,722	6,914	6,532
Cash generated from operating activities before interest and income taxes:	163,636	119,677	124,322
Income taxes paid	(27,265)	(29,462)	(22,472)
Interest paid	(3,390)	(84)	(215)
Interest received	3,327	2,004	1,232
Net cash provided by operating activities	136,308	92,135	102,867
Cash flows from investing activities:
Restricted cash, held in escrow		(5,112)
Payment of contingent considerations in relation to acquisitions	(5,465)
Proceeds from restricted cash, held in escrow	239	280
Government grant received	200
Government grants repaid	(136)
Purchase of property and equipment and intangible assets	(33,684)	(22,867)	(27,455)
Investment in mutual funds	(52)	(462)
Marketable securities (purchased)/sold, net	(12,761)	32,413	(29,616)
Proceeds from sale of property and equipment	367	443	329
Investment in fixed deposits	(26,532)	(24,672)	(14,791)
Proceeds from maturity of fixed deposits	30,698	15,112	8,828
Dividends received	3,570	4,127	5,040
Proceeds from maturity of fixed maturity plans ("FMPs")	100		30,115
Net cash used in investing activities	(43,583)	(131,267)	(30,122)
Cash flows from financing activities:
Buyback of shares	(39,546)	(64,224)	(30,461)
Proceeds from exercise of stock options	1,347	8,941	1,303
Proceeds from long term debt		118,000
Payment of debt issuance cost	(354)	(953)
Repayment of long term debt	(28,100)		(13,163)
Repayments of short term borrowings, net		(475)	(13,058)
Purchase of equity of non-controlling interest	(52)
Excess tax benefit from share-based compensation expense	685	270	229
Net cash (used in)/provided by financing activities	(66,020)	61,559	(55,150)
Exchange difference on cash and cash equivalents	3,321	5,522	(8,189)
Net change in cash and cash equivalents	30,026	27,949	9,406
Cash and cash equivalents at the beginning of the year	69,803	41,854	32,448
Cash and cash equivalents at the end of the year	99,829	69,803	41,854
Non-cash transactions: Investing activities
(i) Liability towards property and equipment and intangible assets purchased on credit	5,440	4,292	4,528
(ii) Contingent consideration payable towards acquisitions		19,678
(iv) Release of restricted cash, held in escrow	(1,535)
MTS HealthHelp Inc. [member]
Cash flows from investing activities:
Acquisition of subsidiaries and businesses, net of cash acquired		(56,674)
Adjustment towards acquisition	(573)
Repayment of long-term debt of subsidiaries		(29,249)
Denali Sourcing Services Inc. [member]
Cash flows from investing activities:
Acquisition of subsidiaries and businesses, net of cash acquired		(31,886)
Adjustment towards acquisition	446
Non-cash transactions: Investing activities
(iii) Liability towards deferred consideration		522
Non-cash transactions: Financing activities
(i) Short term line of credit		475
Value Edge Research Services Private Limited [member]
Cash flows from investing activities:
Acquisition of subsidiaries and businesses, net of cash acquired		$ (12,720)
Non-cash transactions: Investing activities
(iv) Release of restricted cash, held in escrow	$ (1,535)
Telkom SA SOC Limited [member]
Cash flows from investing activities:
Acquisition of subsidiaries and businesses, net of cash acquired			$ (2,572)

Consolidated Statements of Cas8

Consolidated Statements of Cash Flows (Parenthetical) - Long term debt (including current portion) [member] $ in Thousands	12 Months Ended
	Mar. 12, 2018USD ($)
Opening Balance	$ 116,743
Cash flows	(28,100)
Non-cash changes amortization of debt issuance cost	488
Closing balance	$ 89,131

Company overview

Company overview	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Company overview	1. Company overview WNS (Holdings) Limited (“WNS Holdings”), along with its subsidiaries (collectively, “the Company”), is a global business process management (“BPM”) company with client service offices in Australia, Dubai (United Arab Emirates), Germany, London (UK), New Jersey (US), New Zealand, Singapore and Switzerland and delivery centers in the People’s Republic of China (“China”), Costa Rica, India, the Philippines, Poland, Romania, Republic of South Africa (“South Africa”), Sri Lanka, Turkey, the United Kingdom (“UK”) and the United States (“US”). The Company’s clients are primarily in the travel, shipping and logistics services; utilities, retail and consumer products group; banking and financial, healthcare and insurance and consulting and professional services industries. During the year ended March 31, 2017, the Company completed certain acquisitions (Refer Note 4). WNS Holdings is incorporated in Jersey, Channel Islands and maintains a registered office in Jersey at 22, Grenville Street, St Helier, Jersey JE4 8PX. These consolidated financial statements were approved by the Board of Directors and authorized for issue on May 16, 2018.

Summary of significant accounti

Summary of significant accounting policies	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of significant accounting policies	2. Summary of significant accounting policies a. Basis of preparation These consolidated financial statements have been prepared in compliance with International Financial Reporting Standards (“IFRS”) as issued by the International Accounting Standard Board (“IASB”). These consolidated financial statements correspond to the classification provisions contained in IAS 1 (revised), “Presentation of Financial Statements.” Accounting policies have been applied consistently to all periods presented in these consolidated financial statements. b. Basis of measurement These consolidated financial statements have been prepared on a historical cost convention and on an accrual basis, except for the following material items that have been measured at fair value as required by relevant IFRS:- a. Derivative financial instruments; b. Share-based payment transactions; c. Marketable securities and investments in mutual funds; d. Investments in fixed maturity plans (FMPs); and e. Contingent consideration. c. Use of estimates and judgments The preparation of financial statements in conformity with IFRS requires management to make judgments, estimates and assumptions that affect the application of accounting policies and the reported amount of assets, liabilities, income and expenses. Actual results may differ from those estimates. Estimates and underlying assumptions are reviewed on an ongoing basis. Revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future period affected. In particular, information about significant areas of estimation, uncertainty and critical judgments in applying accounting policies that have the most significant effect on the amount recognized in the consolidated financial statements is included in the following notes: i. Revenue recognition The Company provides automobile claims handling services, wherein the Company enters into contracts with its clients to process all their claims over the contract period and the fees are determined either on a per claim basis or as a fixed payment for the contract period. Where the contracts are on a per claim basis, the Company invoices the client at the inception of the claim process. The Company estimates the processing period for the claims and recognizes revenue over the estimated processing period. This processing period generally ranges between one to two months. The processing time may be greater for new clients and the estimated service period is adjusted accordingly. The processing period is estimated based on historical experience and other relevant factors, if any. ii. Allowance for doubtful trade recevables The allowance for doubtful trade receivables is evaluated on a regular basis and adjusted based upon management’s best estimate of probable losses inherent in trade receivable. In estimating probable losses, the Company reviews accounts that are past due, non-performing iii. Current income taxes The major tax jurisdictions for the Company are India, South Africa, UK and US, though the Company also files tax returns in other foreign jurisdictions. Significant judgments are involved in determining the provision for income taxes including judgment on whether tax positions are probable of being sustained in tax assessments. A tax assessment can involve complex issues, which can only be resolved over extended time periods. The recognition of taxes that are subject to certain legal or economic limits or uncertainties is assessed individually by management based on the specific facts and circumstances. iv. Deferred income taxes The assessment of the probability of future taxable profit in which deferred tax assets can be utilized is based on the Company’s latest approved budget forecast, which is adjusted for significant non-taxable v. Impairment An impairment loss is recognized for the amount by which an asset’s or cash-generating unit’s carrying amount exceeds its recoverable amount. To determine the recoverable amount, management estimates expected future cash flows from each asset or cash-generating unit and determines a suitable interest rate in order to calculate the present value of those cash flows. In the process of measuring expected future cash flows management makes assumptions about future operating results. These assumptions relate to future events and circumstances. The actual results may vary, and may cause significant adjustments to the Company’s assets within the next financial year. The calculation of impairment loss involves significant estimates and assumptions which includes revenue and earnings multiples, growth rates and net margins used to calculate projected future cash flows, risk-adjusted discount rate, future economic and market conditions. In most cases, determining the applicable discount rate involves estimating the appropriate adjustment to market risk and the appropriate adjustment to asset-specific risk factors. vi. Valuation of derivative financial instruments Management uses valuation techniques in measuring the fair value of derivative financial instruments, where active market quotes are not available. In applying the valuation techniques, management makes maximum use of market inputs, and uses estimates and assumptions that are, as far as possible, consistent with observable data that market participants would use in pricing the instrument. Where applicable data is not observable, management uses its best estimate about the assumptions that market participants would make. These estimates may vary from the actual prices that would be achieved in an arm’s length transaction at the reporting date. vii. Accounting for defined benefit plans In accounting for pension and post-retirement benefits, several statistical and other factors that attempt to anticipate future events are used to calculate plan expenses and liabilities. These factors include expected return on plan assets, discount rate assumptions and rate of future compensation increases. To estimate these factors, actuarial consultants also use estimates such as withdrawal, turnover, and mortality rates which require significant judgment. The actuarial assumptions used by the Company may differ materially from actual results in future periods due to changing market and economic conditions, regulatory events, judicial rulings, higher or lower withdrawal rates, or longer or shorter participant life spans. viii. Share-based compensation expense The share-based compensation expense is determined based on the Company’s estimate of equity instruments that will eventually vest. ix. Business combinations Business combinations are accounted for using the acquisition method under the provisions of IFRS 3 (Revised) , “Business Combinations”. The cost of an acquisition is measured at the fair value of the assets transferred, equity instruments issued and liabilities incurred at the date of acquisition. The cost of the acquisition also includes the fair value of any contingent consideration. Identifiable tangible and intangible assets acquired and liabilities and contingent liabilities assumed in a business combination are measured initially at their fair value on the date of acquisition. Significant estimates are required to be made in determining the value of contingent consideration and intangible assets. d. Basis of consolidation The Company consolidates entities over which it has control. Control exists when the Company has existing rights that give the Company the current ability to direct the activities which affect the entity’s returns; the Company is exposed to or has rights to returns which may vary depending on the entity’s performance; and the Company has the ability to use its power to affect its own returns from its involvement with the entity. Subsidiaries are consolidated from the date control commences until the date control ceases. i. Business combinations Business combinations are accounted for using the acquisition method under the provisions of IFRS 3 (Revised) , “Business Combinations”. The cost of an acquisition is measured at the fair value of the assets transferred, equity instruments issued and liabilities incurred at the date of acquisition. The consideration of the acquisition also includes the fair value of any contingent consideration. Identifiable tangible and intangible assets acquired and liabilities and contingent liabilities assumed in a business combination are measured initially at their fair value on the date of acquisition. Significant estimates are required to be made in determining the value of contingent consideration and intangible assets. Transaction costs that the Company incurs in connection with a business combination such as finders’ fees, legal fees, due diligence fees, and other professional and consulting fees are expensed as incurred. ii. Transactions eliminated on consolidation All significant inter-company and intra-company balances, transactions, income and expenses including unrealized income or expenses are eliminated on consolidation. e. Functional and presentation currency The financial statements of each of the Company’s subsidiaries are presented using the currency of the primary economic environment in which these entities operate (i.e. the functional currency). The consolidated financial statements are presented in US dollars (USD) which is the presentation currency of the Company and has been rounded off to the nearest thousands. f. Foreign currency transactions and translation i. Transactions in foreign currency Transactions in foreign currency are translated into the functional currency using the exchange rates prevailing at the dates of the transactions. Foreign exchange gains and losses resulting from the settlement of such transactions and from the translation at the exchange rates prevailing at the reporting date of monetary assets and liabilities denominated in foreign currencies are recognized in the consolidated statement of income. Gains/losses relating to translation or settlement of trading activities are disclosed under foreign exchange gains/losses and translation or settlements of financing activities are disclosed under finance expenses. In the case of foreign exchange gains/losses on borrowings that are considered as a natural economic hedge for the foreign currency monetary assets, such foreign exchange gains/losses, net are presented within results from operating activities. ii. Foreign operations For the purpose of presenting consolidated financial statements, the assets and liabilities of the Company’s foreign operations that have local functional currency are translated into US dollars using exchange rates prevailing at the reporting date. Income and expense are translated at the monthly average exchange rate for the respective period. Exchange differences arising, if any, are recorded in equity as part of the Company’s other comprehensive income. Such exchange differences are recognized in the consolidated statement of income in the period in which such foreign operations are disposed. Goodwill and fair value adjustments arising on the acquisition of foreign operation are treated as assets and liabilities of the foreign operation and translated at the exchange rate prevailing at the reporting date. Foreign currency exchange differences arising from intercompany receivables or payables relating to foreign operations, the settlement of which is neither planned nor likely to occur in the foreseeable future, are considered to form part of net investment in foreign operation and are recognized in foreign currency translation reserve. g. Financial instruments — initial recognition and subsequent measurement Financial instruments are classified in the following categories: • Non-derivative available-for-sale. • Non-derivative • Derivative financial instruments under the category of financial assets or financial liabilities at FVTPL. The classification of financial instruments depends on the purpose for which those were acquired. Management determines the classification of the Company’s financial instruments at initial recognition. i. Non-derivative a) Loans and receivables Loans and receivables are non-derivative non-current b) Financial assets designated as FVTPL Financial assets at FVTPL include financial assets that are either classified as held for trading if acquired principally for the purpose of selling in the short term or that meet certain conditions and are designated at FVTPL upon initial recognition. Financial assets are initially measured at fair value. Transaction costs directly attributable to the acquisition of financial assets at fair value through profit or loss are recognized immediately in profit or loss. Assets in this category are measured at fair value with changes therein recognized in profit or loss. The fair values of financial assets in this category are determined by reference to active market transactions or using a valuation technique where no active market exists. Assets in this category are classified as current assets if expected to be settled within 12 months, otherwise they are classified as non-current. c) Available-for-sale Available-for-sale non-derivative Available-for-sale ii. Non-derivative All financial liabilities are recognized initially at fair value, except in the case of loans and borrowings which are recognized at fair value net of directly attributable transaction costs. The Company’s financial liabilities include trade and other payables, bank overdrafts, contingent consideration and loans and borrowings. Trade and other payables maturing later than 12 months after the reporting date are presented as non-current After initial recognition, interest bearing loans and borrowings are subsequently measured at amortized cost using the effective interest rate method. Gains and losses are recognized in the consolidated statement of income when the liabilities are derecognized as well as through the effective interest rate method amortization process. After initial recognition, contingent consideration are subsequently measured at fair value and the changes to the fair value are recognized in the consolidated statement of income. iii. Derivative financial instruments and hedge accounting The Company is exposed to foreign currency fluctuations on foreign currency assets, liabilities, net investment in foreign operations and forecasted cash flows denominated in foreign currency. The Company limits the effect of foreign exchange rate fluctuation by following established risk management policies including the use of derivatives. The Company enters into derivative financial instruments where the counter party is a bank. The Company holds derivative financial instruments such as foreign exchange forward, option contracts and interest rate swaps to hedge certain foreign currency and interest rate exposures. Cash flow hedges The Company recognizes derivative instruments as either assets or liabilities in the statement of financial position at fair value. Derivative instruments qualify for hedge accounting when the instrument is designated as a hedge; the hedged item is specifically identifiable and exposes the Company to risk; and it is expected that a change in fair value of the derivative instrument and an opposite change in the fair value of the hedged item will have a high degree of correlation. For derivative instruments where hedge accounting is applied, the Company records the effective portion of derivative instruments that are designated as cash flow hedges in other comprehensive income (loss) in the statement of comprehensive income, which is reclassified into earnings in the same period during which the hedged item affects earnings. The remaining gain or loss on the derivative instrument in excess of the cumulative change in the present value of future cash flows of the hedged item, if any (i.e., the ineffective portion) or hedge components excluded from the assessment of effectiveness, and changes in fair value of other derivative instruments not designated as qualifying hedges is recorded as gains/losses, net in the consolidated statement of income. Gains/losses on cash flow hedges on intercompany forecasted revenue transactions are recorded in foreign exchange gains/losses and cash flow hedge on interest rate swaps are recorded in finance expense. Cash flows from the derivative instruments are classified within cash flows from operating activities in the statement of cash flows. iv. Offsetting of financial instruments Financial assets and financial liabilities are offset against each other and the net amount reported in the consolidated statement of financial position if, and only if, there is a currently enforceable legal right to offset the recognized amounts and there is an intention to settle on a net basis, or to realize the assets and settle the liabilities simultaneously. v. Fair value of financial instruments The fair value of financial instruments that are traded in active markets at each reporting date is determined by reference to quoted market prices or dealer price quotations, without any deduction for transaction costs. For financial instruments not traded in an active market, the fair value is determined using appropriate valuation models. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs including interest rate curves, credit risk, foreign exchange rates, and forward and spot prices for currencies. vi. Impairment of financial assets The Company assesses at each reporting date whether there is objective evidence that a financial asset or a group of financial assets is impaired. A financial asset is considered impaired if objective evidence indicates that one or more events have had a negative effect on the estimated future cash flows of that asset. Individually significant financial assets are tested for impairment on an individual basis. The remaining financial assets are assessed collectively in groups that share similar credit risk characteristics. a) Loans and receivables Impairment loss in respect of loans and receivables measured at amortized cost are calculated as the difference between their carrying amount, and the present value of the estimated future cash flows discounted at the original effective interest rate. Such impairment loss is recognized in the consolidated statement of income. b) Available-for-sale Significant or prolonged decline in the fair value of the security below its cost and the disappearance of an active trading market for the security are objective evidence that the security is impaired. An impairment loss in respect of an available-for-sale h. Equity and share capital i. Share capital and share premium The Company has only one class of equity shares. Par value of the equity share is recorded as the share capital and the amount received in excess of par value is classified as share premium. The credit corresponding to the share-based compensation expense and excess tax benefit related to the exercise of share options and restricted share units is recorded in share premium. ii. Retained earnings Retained earnings comprise the Company’s undistributed earnings after taxes. iii. Other components of equity Other components of equity consist of the following: Cash flow hedging reserve Changes in fair value of derivative hedging instruments designated and effective as a cash flow hedge are recognized net of taxes. Foreign currency translation reserve Foreign currency translation reserve consists of (i) the exchange difference arising from the translation of the financial statements of foreign subsidiaries and (ii) foreign currency differences arising from intercompany receivables or payables relating to foreign operations, the settlement of which is neither planned nor likely to occur in the foreseeable future, which are considered to form part of net investment in foreign operation Pension adjustments This reserve represents cumulative actuarial gain and losses recognized, net of taxes on defined benefits plans. i. Cash and cash equivalents The Company considers all highly liquid investments with an initial maturity of up to three months to be cash equivalents. Cash equivalents are readily convertible into known amounts of cash and subject to an insignificant risk of changes in value. j. Investments i. Marketable securities and mutual funds The Company’s marketable securities represent liquid investments and are acquired principally for the purpose of earning daily dividend income. All additions and redemptions of such investments are recognized on the trade date. Investments are initially measured at cost, which is the fair value of the consideration paid, including transaction costs. Marketable securities classified under the Available-for-sale Investments in mutual funds represent investments in mutual fund schemes wherein the mutual fund issuer has invested these funds in enterprise development funds. These investments are carried at fair value, with changes in fair value recognized in other comprehensive income. The fair value represents the original cost of the investment and the investment’s fair value at each reporting period. Investments in mutual funds have been designated as available for sale. ii. Investments in fixed maturity plans The Company’s investments in fixed maturity plans (“FMPs”) represent investments in mutual fund schemes wherein the mutual fund issuer has invested these funds in certificate of deposits with banks in India. The investments in FMPs are designated as fair value through profit or loss and change in fair value is recognized in the consolidated statement of income. The fair value represents original cost of an investment and the investment’s fair value at each reporting period or net asset value (“NAV”) as quoted. The Company manages FMPs on a fair value basis in accordance with the entity’s documented risk management, investment strategy and information provided to the key managerial personnel. The returns on the investment are measured based on the fair value movement rather than looking at the overall returns on the maturity. The Company’s investment purchase and sale decisions are also based on the fair value fluctuations rather than a predetermined policy to hold the investment until maturity. Key management personnel believe that recording these investments through the consolidated statement of income would provide more relevant information to measure the performance of the investment. iii. Investments in fixed deposits Investments in fixed deposits consist of term deposits with original maturities of more than three months with banks. These are designated as Loans and Receivables. k. Funds held for clients Some of the Company’s agreements in the auto claims handling services allow the Company to temporarily hold funds on behalf of the client. The funds are segregated from the Company’s funds and there is usually a short period of time between when the Company receives these funds from the client and when the payments are made on their behalf. l. Property and equipment Property and equipment are stated at historical cost. Cost includes expenditures directly attributable to the acquisition of the asset. Depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets, which are as follows: Asset description Asset life (in years) Buildings 20 Computers and software 3-4 Furniture, fixtures and office equipment 2-5 Vehicles 3 Leasehold improvements Lesser of estimated useful life or lease term Assets acquired under finance leases are capitalized as assets by the Company at an amount equal to the fair value of the leased asset or, if lower, the present value of the minimum lease payments, each determined at the inception of the lease. Assets under finance leases and leasehold improvements are depreciated over the shorter of the lease term or the estimated useful life of the assets. Advances paid towards the acquisition of property and equipment and the cost of property and equipment not ready for use before the reporting date are disclosed as capital work-in-progress The Company assesses property and equipment for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or group of assets may not be recoverable. If any such indication exists, the Company estimates the recoverable amount of the asset. The recoverable amount of an asset or cash generating unit is the higher of its fair value less cost of disposal (“FVLCOD”) and its value-in-use m. Goodwill Goodwill represents the excess of the cost of an acquisition over the fair value of the Company’s share of the net identifiable assets of the acquired subsidiary at the date of acquisition. Goodwill is allocated to the cash-generating units expected to benefit from the synergies of the combination for the purpose of impairment testing. Goodwill is tested, at the cash-generating unit (or group of cash generating units) level, for impairment annually or if events or changes in circumstances indicate that the carrying amount may not be recoverable. Goodwill is carried at cost less accumulated impairment losses. Impairment loss on goodwill is not reversed. See further discussion on impairment testing under “Impairment of intangible assets and goodwill” below. n. Intangible assets Intangible assets are recognized only when it is probable that the expected future economic benefits attributable to the assets will accrue to the Company and the cost can be reliably measured. Intangible assets acquired in a business combination are recorded at fair value using generally accepted valuation methods appropriate for the type of intangible asset. Intangible assets with definite lives are amortized over the estimated useful lives and are reviewed for impairment, if indicators of impairment arise. Intangible assets with indefinite lives are not amortized but instead are tested for impairment at least annually and written down to the fair value. See further discussion on impairment testing under “Impairment of intangible assets and goodwill” below. Software Development Costs Costs incurred for developing software or enhancements to the existing software products to be sold and/or used for internal use are capitalized once the research phase is complete, technological feasibility and commercial feasibility has been established, future economic benefits are probable, the Company has an intention and ability to complete and use or sell the software and the costs can be measured reliably. Technological feasibility is established upon completion of a detailed design program or, in its absence, completion of a working model. Significant management judgments and estimates are utilized in the assessment of when technological feasibility is established, as well as in the ongoing assessment of the recoverability of capitalized costs. Costs that qualify as software development costs include external direct costs of materials and services utilized in developing or obtaining software and compensation and related benefits for employees who are directly associated with the software project. The capitalized costs are amortized on a straight-line basis over the estimated useful life. Costs associated with research phase activities, training, maintenance and all post-implementation stage activities are expensed as incurred. The Company’s definite lived intangible assets are amortized over the estimated useful life of the assets on a straight-line basis, as given below. Asset description Weighted average amortization period (in months) Customer contracts 48 Customer relationships 217 Covenant not-to-compete 48 Trade names 34 Technology 94 Intellectual Property and other rights 24 Software 55 Service mark Indefinite useful o. Impairment of intangible assets and goodwill Goodwill is not subject to amortization and tested at least annually for impairment or whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. Intangible assets that are subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. An impairment loss is recognized for the amount by which the asset’s carrying amount exceeds its recoverable amount. The recoverable amount is the higher of an asset’s FVLCOD and VIU. For the purposes of assessing impairment, assets are grouped at the cash generating unit level which is the lowest level for which there are separately identifiable cash flows. Impairment losses recognized in respect of cash generating units are allocated first to reduce the carrying amount of any goodwill allocated to the cash generating units (or group of cash generating units) and then, to reduce the carrying amount of the other assets in the cash generating unit (or group of cash generating units) on a pro rata basis based on the carrying amount of each asset in the cash generating unit. Intangible assets except goodwill that suffered impairment are reviewed for possible reversal of the impairment at each reporting date. p. Employee benefits i. Defined contribution plans US Savings Plan Eligible employees of the Company in the US participate in a savings plan (“the Plan”) under Section 401(k) of the United States Internal Revenue Code (“the Code”). The Plan allows for employees to defer a portion of their annual earnings on a pre-tax UK Pension Scheme Eligible employees in the UK contribute to a defined contribution pension scheme operated in the UK. The assets of the scheme are held separately in an independently administered fund. The pension expense represents contributions payable to the fund maintained by the Company. Provident Fund Eligible employees of the Company in India, the Philippines, South Africa, Sri Lanka and the UK participate in a defined contribution fund in accordance with the regulatory requirements in the respective jurisdictions. Both the employee and the Company contribute an equal amount to the fund which is equal to a specified percentage of the employee’s salary. The Company has no further obligation under defined contribution plans beyond the contributions made under these plans. Contributions are charged to profit or loss and are included in the consolidated statement of income in the year in which they accrue. ii. Defined benefit plan Employees in India, the Philippines and Sri Lanka are entitled to a defined benefit retirement plan covering eligible employees of the Company. The plan provides for a lump-sum Gratuity liabilities are determined by actuarial valuation, performed by an independent actuary, at each reporting date using the projected unit credit method. The Company recognizes the net obligation of a defined benefit plan in its balance sheet as an asset or liability, as the case may be, in accordance with IAS 19, “Employee Benefits.” iii. Compensated absences The Company’s liability for compensated absences, which are expected to be utilized or settled within one year, is determined on an accrual basis for the carried forward unused vacation balances standing to the credit of each employee as at year-end The Company’s liability for compensated absences, which are expected to be utilized after one year is determined on the basis of an actuarial valuation using the projected unit credit method and is charged to consolidated statement of income in the year in which they accrue. q. Share-based payments The Company accounts for share-based compensation expense relating to share-based payments using a fair value method in accordance with IFRS 2 “Share-based Payments.” r. Provisions and accrued expenses A provision is recognized in the statement of financial position when the Company has a present legal or constructive obligation as a result of a past event, and it is probable that an outflow of economic benefits will be required to settle the obligation. If the effect is material, provisions are recognized at present value by discounting the expected future cash flows at a pre-tax Provisions for onerous contracts are recognized when the expected benefits to be derived by the Company from a contract are lower than the unavoidable costs of meeting the future obligations under the contract. The provision is measured at the present value of the lower of the expected cost of terminating the contract and the expected net cost of continuing with the contract. Before a provision is established, the Company recognizes any impairment loss on the assets associated with that contract. s. Revenue recogniti

New accounting pronouncements n

New accounting pronouncements not yet adopted by the Company	12 Months Ended
	Mar. 31, 2018
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New accounting pronouncements not yet adopted by the Company	3. New accounting pronouncements not yet adopted by the Company Certain new standards, interpretations and amendments to existing standards have been published that are mandatory for the Company’s accounting periods beginning on or after April 1, 2018 or later periods. Those which are considered to be relevant to the Company’s operations are set out below. i. In May 2014, the IASB issued IFRS 15 “Revenue from Contracts with Customers” (IFRS 15). This standard provides a single, principle-based five-step model to be applied to all contracts with customers. Guidance is provided on topics such as the point at which revenue is recognized, accounting for variable consideration, costs of fulfilling and obtaining a contract and various other related matters. IFRS 15 also introduced new disclosure requirements with respect to revenue. The five steps in the model under IFRS 15 are: (i) identify the contract with the customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contracts; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. IFRS 15 replaces the following standards and interpretations: • IAS 11 • IAS 18 • IFRIC 13 • IFRIC 15 • IFRIC 18 • SIC-31 When first applying IFRS 15, it should be applied in full for the current period, including retrospective application to all contracts that were not yet complete at the beginning of that period. In respect of prior periods, the transition guidance allows an option to either: • apply IFRS 15 in full to prior periods (with certain limited practical expedients being available); or • retain prior period figures as reported under the previous standards, recognizing the cumulative effect of applying IFRS 15 as an adjustment to the opening balance of equity as at the date of initial application (beginning of current reporting period). In April 2016, the IASB issued amendments to IFRS 15, clarifying some requirements and providing additional transitional relief for companies. The amendments do not change the underlying principles of IFRS 15 but clarify how those principles should be applied. The amendments clarify how to: • identify a performance obligation (the promise to transfer a good or a service to a customer) in a contract; • determine whether a company is a principal (the provider of a good or service) or an agent (responsible for arranging for the good or service to be provided); and • determine whether the revenue from granting a license should be recognized at a point in time or over time. In addition to the clarifications, the amendments include two additional reliefs to reduce cost and complexity for a company when it first applies IFRS 15. The amendments have the same effective date as IFRS 15. IFRS 15 is effective for fiscal years beginning on or after January 1, 2018. The Company will apply this standard retrospectively with the cumulative effect of initially applying this standard recognized at April 1, 2018 (i.e. the date of initial application in accordance with this standard) which will be based on specific terms of active contracts as at April 1, 2018. The Company evaluated specific terms of such contracts, potential changes to accounting system and processes and additional disclosure requirements that may be necessary. The Company expects revenue recognition across the portfolio of services to remain largely unchanged, however there will be an impact on the timing of recognition of certain contract costs, which will now be amortized over the contract period rather than expensed as incurred. Further, some of the Company’s contracts have provisions primarily with regards to service level arrangements and discounts which the Company needs to estimate at contract inception and account for in revenue. Based on the analysis completed to date, the Company does not currently expect that the adoption will have a material impact on consolidated revenue in its consolidated financial statements. ii. In July 2014, the IASB finalized and issued IFRS 9 – “Financial Instruments” (IFRS 9). IFRS 9 replaces IAS 39 “Financial instruments: recognition and measurement,” the previous Standard which dealt with the recognition and measurement of financial instruments in its entirety upon former’s effective date. Key requirements of IFRS 9: Replaces IAS 39’s measurement categories with the following three categories: • fair value through profit or loss (“FVTPL”) • fair value through other comprehensive income (“FVTOCI”) • amortized cost Eliminates the requirement for separation of embedded derivatives from hybrid financial assets, the classification requirements to be applied to the hybrid financial asset in its entirety. Requires an entity to present the amount of change in fair value due to change in entity’s own credit risk in other comprehensive income. Introduces new impairment model, under which the “expected” credit loss are required to be recognized as compared to the existing “incurred” credit loss model of IAS 39. Fundamental changes in hedge accounting by introduction of new general hedge accounting model which: • Increases the eligibility of hedged item and hedging instruments; • Introduces a more principles–based approach to assess hedge effectiveness. IFRS 9 is effective for annual periods beginning on or after January 1, 2018. Earlier application is permitted provided that all the requirements in the Standard are applied at the same time with two exceptions: (1) The requirement to present changes in the fair value of a liability due to changes in own credit risk may be applied early in isolation; (2) Entity may choose as its accounting policy choice to continue to apply hedge accounting requirements of IAS 39 instead of new general hedge accounting model as provided in IFRS 9. In October 2017, the IASB issued an amendment to IFRS 9 on the modification of financial liabilities measured at amortized cost that does not result in the derecognition of the financial liability. The amendment states that any adjustment to the amortized cost of the financial liability arising from a modification or exchange shall be recognized in the profit or loss at the date of the modification or exchange. A retrospective change of the accounting treatment may therefore become necessary if in the past the effective interest rate was adjusted and not the amortized cost amount. This amendment is to be applied retrospectively for fiscal years beginning on or after January 1, 2019, i.e. one year after the first application of IFRS 9 in its current version and early application is permitted. Additional transitional requirements and corresponding disclosure requirements must be observed when applying the amendments for the first time. The Company is currently evaluating the impact of this amendment on its consolidated financial statements. The Company will adopt this standard effective April 1, 2018 by applying the relief from restating comparative information. The key areas impacted upon adoption of the new standard relates to the presentation of hedging instrument gain or losses on cash flow hedges on intercompany forecasted revenue transactions as part of revenues, accounting for time value of options and the presentation of classification and measurement of the Company’s financial instruments. Based on the analysis completed to date, the Company does not currently expect that the adoption will have a material impact on its consolidated financial statements. iii. In January 2016, the IASB has issued IFRS 16 “Leases” (“IFRS 16”). Key changes in IFRS 16 include: • eliminates the requirement to classify a lease as either operating or finance lease in the books of lessee. • introduces a single lessee accounting model, which requires lessee to recognize assets and liabilities for all leases, initially measured at the present value of unavoidable future lease payment. Entity may elect not to apply this accounting requirement to short term leases and leases for which underlying asset is of low value. • replaces the straight-line operating lease expense model with a depreciation charge for the lease asset (included within operating costs) and an interest expense on the lease liability (included within finance costs). • requires lessee to classify cash payments for principal and interest portion of lease arrangement within financing activities and financing/operating activities respectively in the cash flow statements. • requires entities to determine whether a contract conveys the right to control the use of an identified asset for a period of time to assess whether that contract is, or contains, a lease. IFRS 16 replaces IAS 17, Leases and related interpretations viz. IFRIC 4, “Determining whether an Arrangement contains a Lease;” SIC-15, SIC-27, IFRS 16 substantially carries forward lessor accounting requirements in IAS 17, “Leases.” Disclosures, however, have been enhanced. IFRS 16 is effective for annual reporting periods beginning on or after 1 January 2019. Early application is permitted for entities that apply IFRS 15, “Revenue from Contracts with Customers” at or before the date of initial application of IFRS 16. A lessee shall apply IFRS 16 either retrospectively to each prior reporting period presented or record a cumulative effect of initial application of IFRS 16 as an adjustment to opening balance of equity at the date of initial application. The Company is currently evaluating the impact of this new standard on its consolidated financial statements. iv. In June 2016, the IASB issued amendments in IFRS 2 – “Share-based Payment” to clarify the following: • the accounting for cash-settled share-based payment transactions that include a performance condition should follow the same approach as for equity-settled share-based payment; • the classification of share-based payment transactions with net settlement features for withholding tax obligations should be classified as equity-settled in its entirety, provided the share-based payment would have been classified as equity-settled had it not included the net settlement feature; and • modifications of a share-based payment that changes the transaction from cash-settled to equity-settled to be accounted for as follows: i. the original liability is derecognized; ii. the equity-settled share-based payment is recognized at the modification date fair value of the equity instrument granted to the extent that services have been rendered up to the modification date; and iii. any difference between the carrying amount of the liability at the modification date and the amount recognized in equity should be recognized in the statement of income immediately. The above amendments are effective for annual periods beginning on or after January 1, 2018. Earlier application is permitted. The amendments are to be applied prospectively. However, if an entity applies the amendments retrospectively, it must do so for all of the amendments described above. The Company intends to adopt these amendments prospectively and expects no material impact on its consolidated financial statements. v. In December 2016, the IFRS Interpretations Committee (“IFRIC”) issued amendments to IFRIC 22 – “Foreign Currency Transactions and Advance Consideration” to clarify the exchange rate to use for translation when payments are made or received in advance of the related asset, expense or income (or part of it) in foreign currency. The exchange rate in this case will be the rate prevalent on the date on which an entity initially recognizes the non-monetary non-monetary IFRIC 22 is effective for annual reporting periods beginning on or after January 1, 2018. Earlier application is permitted. On initial application, entities have the choice to apply the Interpretation either retrospectively or, alternatively, prospectively to all assets, expenses and income in the scope of the Interpretation initially recognized on or after: • the beginning of the reporting period in which the entity first applies the Interpretation; or • the beginning of a prior reporting period presented as comparative information in the financial statements of the reporting period in which the entity first applies the Interpretation. The Company intends to adopt these amendments prospectively and expects no material impact on its consolidated financial statements. vi. In June 2017, the IFRIC issued IFRIC 23 – “Uncertainty over Income Tax Treatments” to clarify the accounting for uncertainties in income taxes, by specifically addressing the following: • the determination of whether to consider each uncertain tax treatment separately or together with one or more uncertain tax treatments; • the assumptions an entity makes about the examination of tax treatments by taxations authorities; • the determination of taxable profit (tax loss), tax bases, unused tax losses, unused tax credits and tax rates where there is an uncertainty regarding the treatment of an item; and • the reassessment of judgements and estimates if facts and circumstances change. IFRIC 23 is effective for annual reporting periods beginning on or after 1 January 2019. Earlier application is permitted. On initial application, the requirements are to be applied by recognizing the cumulative effect of initially applying them in retained earnings, or in other appropriate components of equity, at the start of the reporting period in which an entity first applies them, without adjusting comparative information. Full retrospective application is permitted, if an entity can do so without using hindsight. The Company is currently evaluating the impact of this pronouncement on its consolidated financial statements. vii. In February 2018, the IASB issued amendments to IAS 19 – “Employee Benefits” regarding plan amendments, curtailments and settlements. The amendments are as follows: • If a plan amendment, curtailment or settlement occurs, it is now mandatory that the current service cost and the net interest for the period after the remeasurement are determined using the assumptions used for the remeasurement; • In addition, amendments have been included to clarify the effect of a plan amendment, curtailment or settlement on the requirements regarding asset ceiling. The above amendments are effective for annual periods beginning on or after January 1, 2019. Earlier application is permitted but must be disclosed. The Company is currently evaluating the impact of these amendments on its consolidated financial statements.

Business Combinations

Business Combinations	12 Months Ended
	Mar. 31, 2018
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Business Combinations	4. Business Combinations a) HealthHelp On March 15, 2017 (“Acquisition date”), the Company acquired all ownership interests of MTS HealthHelp Inc. and its subsidiaries (“HealthHelp”), which provides benefits management across several specialty healthcare areas, including radiology, cardiology, oncology, sleep care, orthopedics, and pain management, for a total consideration of $68,910, including working capital adjustments of $573 and a contingent consideration of $8,545, payable over a period of two years linked to revenue targets and continuation of an identified client contract. The fair value of the contingent consideration liability was estimated using level 3 inputs which included an assumption for discount rate of 2.5%. The potential undiscounted amount of all future payments that the Company could be required to make under the contingent consideration arrangement is between $0 and $8,876. The Company funded the acquisition primarily with a five year secured term loan. The Company is expected to leverage HealthHelp’s capability in care management to address the needs of payor, provider and insurance organizations. The Company incurred acquisition related costs of $1,809, which have been included in “General and administrative expenses” in the consolidated statement of income for the year ended March 31, 2017. During the year ended March 31, 2018, the Company made a payment of $573 towards working capital adjustments. In March 2018, a contingent consideration of $3,114 was paid by the Company to the sellers on achievement of the revenue target in relation to the identified client contract related to the first measurement period and an amount of $1,324 was reversed and credited to its consolidated income statement, due to the shortfall in revenue target achievement for the identified client contract, in accordance with the terms of the share purchase agreement (“SPA”). The purchase price has been allocated, as set out below, to the assets acquired and liabilities assumed in the business combination. Amount Cash $ 3,119 Trade receivables 4,910 Unbilled revenue 2,016 Prepayments and other current assets 1,060 Property and equipment 4,612 Intangible assets - Software 1,274 - Customer contracts 4,537 - Customer relationships 49,584 - Service mark 400 - Covenant not-to-compete 4,693 - Technology 4,852 Non-current 161 Term loan (29,249 ) Current liabilities (2,555 ) Non-current (1,423 ) Deferred tax liability (18,163 ) Net assets acquired $ 29,828 Less: Purchase consideration 68,910 Goodwill on acquisition $ 39,082 Goodwill of $14,876 arising from this acquisition is expected to be deductible for tax purposes. Goodwill is attributable mainly to expected synergies and assembled workforce arising from the acquisition. During the year ended March 31, 2018, the Company has completed the accounting of the assets acquired and liabilities assumed on acquisition. Corresponding changes to the comparatives for the year ended March 31, 2017 have not been made, as the impact of the change on finalization of purchase price allocation is not material to the Company’s statement of financial position or statement of income. b) Denali Sourcing Services Inc. On January 20, 2017 (“Acquisition Date”), the Company acquired all outstanding shares of Denali Sourcing Services Inc. (“Denali”), a provider of strategic procurement BPM solutions for a purchase consideration of $38,668 (including the contingent consideration of $6,277, dependent on the achievement of revenue targets over a period of three years and deferred consideration of $522 payable in first quarter of fiscal 2018), including adjustments for working capital. The fair value of the contingent consideration liability was estimated using Level 3 inputs which included an assumption for discount rate of 2.5%. The potential undiscounted amount of all future payments that the Company could be required to make under the contingent consideration arrangement is between $0 and $6,578. The payment was funded through a three-year secured term loan. Denali delivers global sourcing and procurement services to high-tech, retail and Consumer Packaged Goods (“CPG”), banking and financial services, utilities, and healthcare verticals. The acquisition of Denali is expected to add a strategic procurement capability to the Company’s existing Finance and Accounting services and will enable the Company to offer procurement solutions to its clients. The Company incurred acquisition related costs of $502, which have been included in “General and administrative expenses” in the consolidated statement of income for the year ended March 31, 2017. During the year ended March 31, 2018, the Company made payment of $522 towards deferred consideration and an amount of $968 was reduced from the purchase consideration towards working capital adjustments. In January 2018, a contingent consideration of $2,351 was paid by the Company to the sellers on achievement of the revenue target related to the first measurement period. The purchase price has been allocated, as set out below, to the assets acquired and liabilities assumed in the business combination. Amount Cash $ 1,204 Trade receivables 2,799 Unbilled revenue 1,258 Prepayments and other current assets 95 Property and equipment 53 Deferred tax asset 18 Intangible assets - Software 3 - Customer contracts 3,025 - Customer relationships 8,000 - Trade name 545 - Covenant not-to-compete 1,718 Non-current 27 Current liabilities (3,781 ) Short-term line of credit (475 ) Non-current (343 ) Deferred tax liability (5,020 ) Net assets acquired $ 9,126 Less: Purchase consideration 38,668 Goodwill on acquisition $ 29,542 Goodwill arising from this acquisition is not expected to be deductible for tax purposes. Goodwill is attributable mainly to expected synergies and assembled workforce arising from the acquisition. During the year ended March 31, 2018, the Company has completed the accounting of the assets acquired and liabilities assumed on acquisition. Corresponding changes to the comparatives for the year ended March 31, 2017 have not been made, as the impact of the change on finalization of purchase price allocation is not material to the Company’s statement of financial position or statement of income. c) Value Edge On June 14, 2016 (“Acquisition Date”), the Company acquired all outstanding equity shares of Value Edge Research Services Private Limited (“Value Edge”) which provides business research and analytics reports and databases across the domains of pharmaceutical, biotech and medical devices, for a total consideration of $18,265 including working capital adjustments of $765 and contingent consideration of $5,112 (held in escrow), subject to compliance with certain conditions, payable over a period of three years. The acquisition is expected to deepen the Company’s domain and specialized analytical capabilities in the growing pharma market, and provide the Company with a technology asset, which is leverageable across clients and industries. The Company incurred acquisition related costs of $24, which have been included in “General and administrative expenses” in the consolidated statement of income for the year ended March 31, 2017. During the year ended March 31, 2018, the Company released from escrow an amount of $1,535 towards contingent consideration to the sellers. The purchase price has been allocated, as set out below, to the assets acquired and liabilities assumed in the business combination. Amount Cash $ 432 Trade receivables 370 Unbilled revenue 706 Investments 87 Prepayments and other current assets 99 Property and equipment 78 Deferred tax asset 49 Intangible assets - Software 10 - Customer contracts 701 - Customer relationships 1,894 - Trade name 104 - Covenant not-to-compete 2,655 - Technology 1,238 Non-current 74 Current liabilities (1,236 ) Non-current (126 ) Deferred tax liability (2,281 ) Net assets acquired $ 4,854 Less: Purchase consideration 18,265 Goodwill on acquisition $ 13,411 Goodwill arising from this acquisition is not expected to be deductible for tax purposes (Refer Note 23). Goodwill is attributable mainly to expected synergies and assembled workforce arising from the acquisition. d) Telkom On April 10, 2015, the Company entered into an agreement with Telkom SA SOC LIMITED (“Telkom”), a leading provider of communication services in South Africa, pursuant to which the Company agreed to acquire a contract and the related workforce of Telkom effective May 1, 2015 (“Acquisition Date”). The net purchase price of the transaction, which was paid in cash, was ZAR 35,639 ($2,572 based on the exchange rate on September 30, 2015). The purchase price has been allocated as follows: Amount Customer contract- intangible assets $ 2,990 Cash 411 Accrued leave liability (411 ) Deferred tax liabilities (837 ) Net assets acquired $ 2,153 Less: Purchase consideration 3,331 Goodwill on acquisition $ 1,178 Goodwill arising from this acquisition is not expected to be deductible for tax purposes. Goodwill is attributable mainly to benefit from expected synergies and the assembled workforce of Telkom.

Cash and cash equivalents

Cash and cash equivalents	12 Months Ended
	Mar. 31, 2018
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Cash and cash equivalents	5. Cash and cash equivalents The Company considers all highly liquid investments with an initial maturity of up to three months to be cash equivalents. Cash and cash equivalents consist of the following: As at March 31, March 31, 2018 2017 Cash and bank balances $ 47,738 $ 46,110 Short term deposits with banks 52,091 23,693 Total $ 99,829 $ 69,803 Short term deposits can be withdrawn by the Company at any time without prior notice and are readily convertible into known amounts of cash with an insignificant risk of changes in value.

Investments

Investments	12 Months Ended
	Mar. 31, 2018
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Investments	6. Investments Investments consist of the following: As at March 31, March 31, 2018 2017 Investments in marketable securities and mutual funds (1) $ 99,954 $ 87,652 Investments in FMPs — 96 Investment in fixed deposits 21,548 24,673 Total $ 121,502 $ 112,421 Note: (1) Marketable securities represent short term investments made principally for the purpose of earning dividend income. As at March 31, 2018 March 31, 2017 Current investments $ 120,960 $ 111,992 Non-current 542 429 Total $ 121,502 $ 112,421

Trade receivables, net

Trade receivables, net	12 Months Ended
	Mar. 31, 2018
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Trade receivables, net	7. Trade receivables, net Trade receivables consist of the following: As at March 31, March 31, 2018 2017 Trade receivables $ 71,952 $ 62,136 Less: Allowances for doubtful trade receivable (564 ) (1,713 ) Total $ 71,388 $ 60,423 The movement in the allowances for doubtful trade receivable is as follows: Year ended March 31, 2018 2017 2016 Balance at the beginning of the year $ 1,713 $ 4,446 $ 5,336 Charged to operations 2,115 777 1,010 Write-offs, net of collections (1,136 ) (2,571 ) (936 ) Reversals (2,321 ) (664 ) (904 ) Translation adjustment 193 (275 ) (60 ) Balance at the end of the year $ 564 $ 1,713 $ 4,446

Prepayments and other assets

Prepayments and other assets	12 Months Ended
	Mar. 31, 2018
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Prepayments and other assets	8. Prepayments and other assets Prepayment and other assets consist of the following: As at March 31, 2018 March 31, 2017 Current: Service tax and other tax receivables $ 6,569 $ 8,029 Deferred transition cost 571 423 Employee receivables 1,099 1,215 Advances to suppliers 2,877 2,087 Prepaid expenses 7,994 8,819 Restricted cash, held in escrow (Refer Note 4(c)) 1,535 1,611 Other assets 4,202 5,201 Total $ 24,847 $ 27,385 Non-current: Deposits $ 8,708 $ 7,569 Income tax assets 12,595 10,202 Service tax and other tax receivables 11,410 6,236 Deferred transition cost 2,467 365 Restricted cash, held in escrow (Refer Note 4(c)) 1,535 3,222 Others assets 5,673 4,350 Total $ 42,388 $ 31,944

Goodwill

Goodwill	12 Months Ended
	Mar. 31, 2018
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Goodwill	9. Goodwill A suumary of the carrying value of goodwill is as follows: As at March 31, March 31, 2018 2017 Gross carrying amount $ 159,500 $ 155,681 Accumulated impairment of goodwill (24,314 ) (21,673 ) Total $ 135,186 $ 134,008 The movement in goodwill balance by reportable segment as at March 31, 2018 and 2017 is as follows: Gross carrying amount WNS WNS Auto Global BPM Claims BPM Total Balance as at April 1, 2016 $ 46,503 $ 29,739 $ 76,242 Goodwill initially arising on acquisitions 82,127 — 82,127 Foreign currency translation 1,248 (3,936 ) (2,688 ) Balance as at March 31, 2017 $ 129,878 $ 25,803 $ 155,681 Goodwill arising on acquisitions (92 ) — (92 ) Foreign currency translation 767 3,144 3,911 Balance as at March 31, 2018 $ 130,553 $ 28,947 $ 159,500 Accumulated impairment losses WNS WNS Auto Global BPM Claims BPM Total Balance as at April 1, 2016 $ — $ — $ — Impairment of goodwill recognized during the year — 21,673 21,673 Balance as at March 31, 2017 $ — $ 21,673 $ 21,673 Impairment of goodwill recognized during the year — — — Foreign currency translation adjustment — 2,641 2,641 Balance as at March 31, 2018 — 24,314 24,314 The carrying value of goodwill allocated to the cash generating units (“CGU”) is as follows: As at March 31, March 31, 2018 2017 WNS Global BPM* $ 3,815 $ 3,815 South Africa 5,581 4,963 Research & Analytics 48,901 49,146 Technology services 3,632 3,238 WNS Auto Claims BPM 4,633 4,130 Finance and accounting 29,542 29,874 Healthcare 39,082 38,842 $ 135,186 $ 134,008 * Excluding South Africa, Research & analytics, Technology services, Finance and accounting and Healthcare goodwill. Key assumptions on which the Company has based its determination of VIUs include: a) Estimated cash flows for five years based on approved internal management budgets with extrapolation for the remaining period, wherever such budgets were shorter than five years period. b) Terminal value arrived by extrapolating last forecasted year cash flows to perpetuity using long-term growth rates. These long-term growth rates take into consideration external macro-economic sources of data. Such long-term growth rate considered does not exceed that of the relevant business and industry sector. c) The discount rates used are based on weighted average cost of capital of a comparable market participant, which are adjusted for specific country risks. The key assumptions used in performing the impairment test, by each CGU, were as follows: CGU’s WNS Global BPM* South Africa Finance & accounting Research & analytics Healthcare Technology services WNS Auto Claims BPM Discount rate 16.0 % 17.1 % 15.1 % 16.0 % 13.0 % 14.0 % 14.0 % Perpetual growth rate 3.0 % 3.0 % 2.0 % 3.0 % 2.5 % 3.0 % 2.0 % * Excluding South Africa, Research & analytics, Technology services, Healthcare and Finance & Accounting. The assumptions used were based on the Company’s internal budget. The Company projected revenue, operating margins and cash flows for a period of five years and applied a perpetual long-term growth rate thereafter. In arriving at its forecasts, the Company considered past experience, economic trends and inflation as well as industry and market trends. The projections also took into account factors such as the expected impact from new client wins and expansion from existing clients businesses and efficiency initiatives, and the maturity of the markets in which each business operates. Based on the above, no impairment was identified as of March 31, 2018 as the recoverable amount of the CGUs exceeded the carrying value. An analysis of the calculation’s sensitivity to a change in the key parameters (revenue growth, operating margin, discount rate and long-term growth rate) did not identify any probable scenarios where the other CGU’s recoverable amount would fall below its carrying amount. Impairment charge recognized in the year March 31, 2017 During the fourth quarter of fiscal 2017, the proposed changes in UK laws with respect to personal injury market and the associated uncertainty of the future earnings trajectory of the legal services business and downward revision in the expectation for future performance within WNS Auto Claims reportable segment due to contract renegotiations and loss of certain clients caused the financial projections and estimates of WNS Auto Claims BPM reportable segment to significantly decrease from the previous estimates which led to an impairment loss during fiscal 2017. These factors arising in the fourth quarter of fiscal 2017 had a significant and negative impact on the VIU of the WNS Auto Claims BPM reportable segment, and the Company determined that the carrying value of the reportable segment for WNS Auto Claims BPM exceeded the VIU as of the date of its annual impairment review. The Company further performed the valuation of FVLCOD of the impairment test. The Company determined the FVLCOD of reportable segment using the “Income Approach — Discounted Cash Flow Analysis” method. Under the “Income Approach — Discounted Cash Flow Analysis” method the key assumptions consider projected sales, cost of sales, and operating expenses for five years. These assumptions were determined by management utilizing our internal operating plan, growth rates for revenues and operating expenses, and margin assumptions using market participant perspective. An additional key assumption under this approach is the discount rate, which represents the expected return on capital and is based on the estimated weighted average cost of capital for a market participant. If our assumptions relative to growth rates were to change, our fair value calculation may change, which could impact the results. The fair value of the WNS Auto Claims BPM reportable segment was determined using Level 3 inputs through an income approach which includes assumptions for discount rate of 13.0% with annual and perpetual growth rate of 2.5% and 2.0% respectively. The Company used the “Market approach-Guideline Public Company Method” to corroborate the results of the income approach. The FVLCOD was higher than the VIU, which is considered as the recoverable amount of the CGU amounting to $37,836 (after deducting costs of disposal of $656). The next step of the goodwill impairment test resulted in an impairment charge of $21,673 for goodwill related to the WNS Auto Claims BPM reportable segment in fiscal 2017. This impairment charge of $21,673 was recorded in operating expenses in the consolidated statement of income, which reduced the goodwill in WNS Auto Claims BPM to $4,130 as at March 31, 2017.

Intangible assets

Intangible assets	12 Months Ended
	Mar. 31, 2018
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Intangible assets	10. Intangible assets The changes in the carrying value of intangible assets for the year ended March 31, 2017 are as follows: Gross carrying value Customer contracts Customer relationships Intellectual property rights Trade names Technology Leasehold benefits Covenant not-to- compete Service mark Software Total Balance as at April 1, 2016 $ 156,786 $ 63,147 $ 4,450 $ — $ — $ 1,835 $ 326 — $ 19,760 $ 246,304 Additions — — — — — — — — 4,611 4,611 On acquisition (Refer Note (4(a),(b),(c)) 8,263 59,478 — 649 6,090 — 9,066 400 1,287 85,233 Translation adjustments 1,952 (703 ) (589 ) 4 41 — 59 — (72 ) 692 Balance as at March 31, 2017 $ 167,001 $ 121,922 $ 3,861 $ 653 $ 6,131 $ 1,835 $ 9,451 $ 400 $ 25,586 $ 336,840 Accumulated amortization Balance as at April 1, 2016 $ 145,483 $ 58,992 $ 4,450 $ — $ — $ 1,835 $ 326 $ — $ 8,101 $ 219,187 Amortization 10,653 4,016 — 78 167 — 650 — 4,975 20,539 Translation adjustments 1,840 (833 ) (589 ) 2 5 — (12 ) — 77 490 Balance as at March 31, 2017 $ 157,976 $ 62,175 $ 3,861 $ 80 $ 172 $ 1,835 $ 964 $ — $ 13,153 $ 240,216 Net carrying value as at March 31, 2017 $ 9,025 $ 59,747 $ — $ 573 $ 5,959 $ — $ 8,487 $ 400 $ 12,433 $ 96,624 The changes in the carrying value of intangible assets for the year ended March 31, 2018 are as follows: Gross carrying value Customer contracts Customer relationships Intellectual Property and other rights Trade names Technology Leasehold benefits Covenant not-to- compete Service mark Software Total Balance as at April 1, 2017 $ 167,001 $ 121,922 $ 3,861 $ 653 $ 6,131 $ 1,835 $ 9,451 400 $ 25,586 $ 336,840 Additions — — 250 — — — — — 7,369 7,619 Translation adjustments 93 940 470 — (6 ) — 10 — 894 2,401 Balance as at March 31, 2018 $ 167,094 $ 122,862 $ 4,581 $ 653 $ 6,125 $ 1,835 $ 9,461 $ 400 $ 33,849 $ 346,860 Accumulated amortization Balance as at April 1, 2017 $ 157,976 $ 62,175 $ 3,861 $ 80 $ 172 $ 1,835 $ 964 $ — $ 13,153 $ 240,216 Amortization 2,725 3,700 74 236 790 — 2,310 — 5,670 15,505 Translation adjustments (62 ) 873 470 (1 ) (4 ) — 12 — 199 1,487 Balance as at March 31, 2018 $ 160,639 $ 66,748 $ 4,405 $ 315 $ 958 $ 1,835 $ 3,286 $ — $ 19,022 $ 257,208 Net carrying value as at March 31, 2018 $ 6,455 $ 56,114 $ 176 $ 338 $ 5,167 $ — $ 6,175 $ 400 $ 14,827 $ 89,652 As at March 31, 2018, the estimated remaining weighted average amortization periods for definite lived intangible assets are as follows: Balance life (In months) Customer contracts 29 Customer relationships 196 Covenant not-to-compete 33 Trade names 21 Technology 80 Intellectual Property and other rights 17 Software 24 The estimated annual amortization expense based on remaining weighted average amortization periods for intangible assets and exchange rates, each as at March 31, 2018 are as follows: Amount 2019 $ 15,279 2020 14,204 2021 9,700 2022 6,095 2023 5,047 Thereafter 38,927 $ 89,252 * * excludes service mark, as it has an indefinite useful life

Property and equipment

Property and equipment	12 Months Ended
	Mar. 31, 2018
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Property and equipment	11. Property and equipment The changes in the carrying value of property and equipment for the year ended March 31, 2017 are as follows: Gross carrying value Buildings Computers and software Furniture, fixtures and office equipment Vehicles Leasehold improvements Total Balance as at April 1, 2016 $ 10,150 $ 69,203 $ 60,860 $ 459 $ 52,589 $ 193,261 Additions — 4,411 7,455 135 8,105 20,106 On acquisition (Refer Note 4(a),(b),(c)) — 1,014 1,895 14 1,820 4,743 Disposals/retirements — (3,407 ) (1,619 ) (33 ) (1,723 ) (6,782 ) Translation adjustments 96 (1,350 ) 286 12 201 (755 ) Balance as at March 31, 2017 $ 10,246 $ 69,871 $ 68,877 $ 587 $ 60,992 $ 210,573 Accumulated depreciation Balance as at April 1, 2016 $ 3,661 $ 58,768 $ 47,375 $ 347 $ 36,874 $ 147,025 Depreciation 505 5,742 5,126 92 5,438 16,903 Disposals/retirements — (3,327 ) (1,241 ) (20 ) (1,354 ) (5,942 ) Translation adjustments 42 (1,372 ) 171 10 222 (927 ) Balance as at March 31, 2017 $ 4,208 $ 59,811 $ 51,431 $ 429 $ 41,180 $ 157,059 Capital work-in-progress 1,282 Net carrying value as at March 31, 2017 $ 54,796 The changes in the carrying value of property and equipment for the year ended March 31, 2018 are as follows: Gross carrying value Buildings Computers and software Furniture, fixtures and office equipment Vehicles Leasehold improvements Total Balance as at April 1, 2017 $ 10,246 $ 69,871 $ 68,877 $ 587 $ 60,992 $ 210,573 Additions — 4,597 9,389 93 9,756 23,835 Disposals/retirements — (3,350 ) (1,718 ) (29 ) (2,303 ) (7,400 ) Translation adjustments (23 ) 1,965 839 5 721 3,507 Balance as at March 31, 2018 $ 10,223 $ 73,083 $ 77,387 $ 656 $ 69,166 $ 230,515 Accumulated depreciation Balance as at April 1, 2017 $ 4,208 $ 59,811 $ 51,431 $ 429 $ 41,180 $ 157,059 Depreciation 514 6,442 6,623 97 6,278 19,954 Disposals/retirements — (3,345 ) (1,674 ) (30 ) (2,308 ) (7,357 ) Translation adjustments (12 ) 1,822 512 1 296 2,619 Balance as at March 31, 2018 $ 4,710 $ 64,730 $ 56,892 $ 497 $ 45,446 $ 172,275 Capital work-in-progress 2,366 Net carrying value as at March 31, 2018 $ 60,606 Certain property and equipment are pledged as collateral against borrowings with a carrying amount of $107 and $170 as at March 31, 2018 and 2017, respectively.

Loans and borrowings

Loans and borrowings	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Loans and borrowings	12. Loans and borrowings Long-term debt The long-term loans and borrowings consist of the following: As at March 31, 2018 March 31, 2017 Currency Interest rate Final maturity ( fiscal year) Foreign currency Total Foreign currency Total US dollars 3M USD Libor +1.27% 2020 $ — 22,700 — 34,000 US dollars 3M USD Libor +0.95% 2022 $ — 67,200 — 84,000 Total 89,900 118,000 Less: Debt issuance cost 769 1,257 Total 89,131 116,743 Current portion of long term debt $ 27,740 $ 27,613 Long term debt $ 61,391 $ 89,130 The Company has entered into a floating to fixed interest rate swap in relation to these debts. In January 2017, WNS North America Inc. obtained from BNP Paribas, Hong Kong, a three-year term loan facility of $34,000 at an interest rate equal to the three-month US dollar LIBOR plus a margin of 1.27% per annum to finance the acquisition of Denali Sourcing Services Inc. WNS North America Inc. has pledged its shares of Denali Sourcing Services Inc. as security for the loan. In connection with the term loan, the Company has entered into an interest rate swap with a bank to swap the variable portion of the interest based on three-month US dollar LIBOR to a fixed rate of 1.5610%. The facility agreement for the term loan contains certain financial covenants as defined in the facility agreement. This term loan is repayable in six semi-annual installments. The first five repayment installments are $5,650 each and the sixth and final repayment installment is $5,750. On July 20, 2017 and January 22, 2018, the Company made scheduled repayments of $5,650 each. As at March 31, 2018, the Company has complied with the financial covenants in all material respects in relation to this loan facility. In March 2017, WNS (Mauritius) Limited obtained from HSBC Bank (Mauritius) Ltd. and Standard Chartered Bank, UK a five-year term loan facility of $84,000 at an interest rate equal to the three-month US dollar LIBOR plus a margin of 0.95% per annum to finance the acquisition of HealthHelp. The Company has pledged its shares of WNS (Mauritius) Limited as security for the loan. In connection with the term loan, the Company has entered into interest rate swaps with banks to swap the variable portion of the interest based on three-month US dollar LIBOR to a fixed rate of 1.9635%. The facility agreement for the term loan contains certain financial covenants as defined in the facility agreement. This term loan is repayable in ten semi-annual installments of $8,400 each. On September 14, 2017 and March 14, 2018, the Company made scheduled repayments of $8,400 each. As at March 31, 2018, the Company has complied with the financial covenants in all material respects in relation to this loan facility. The Company has pledged trade receivables, other financial assets, property and equipment, intangible and other assets with an aggregate amount of $113,174 and $88,730 as of March 31, 2018 and March 31, 2017 respectively, as collateral for the above borrowings. Short-term lines of credit The Company’s Indian subsidiary, WNS Global Services Private Limited (“WNS Global”), has unsecured lines of credit with banks amounting to $62,718 (based on the exchange rate on March 31, 2018). The Company has also established a line of credit in the UK amounting to $13,840 (based on the exchange rate on March 31, 2018). Further the Company has also established a line of credit in South Africa amounting to $1,732 (based on the exchange rate on March 31, 2018). As at March 31, 2018, no amounts were drawn under these lines of credit.

Financial instruments

Financial instruments	12 Months Ended
	Mar. 31, 2018
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Financial instruments	13. Financial instruments Financial instruments by category The carrying value and fair value of financial instruments by class as at March 31, 2018 are as follows: Financial assets Loans and receivables Financial assets at FVTPL Derivative designated as cash flow hedges (carried at fair value) Available for sale Total carrying value Total fair value Cash and cash equivalents $ 99,829 $ — $ — $ — $ 99,829 $ 99,829 Investment in fixed deposits 21,548 — — — 21,548 21,548 Investments in marketable securities and mutual funds — — — 99,954 99,954 99,954 Trade receivables 71,388 — — — 71,388 71,388 Unbilled revenue 61,721 — — — 61,721 61,721 Funds held for clients 10,066 — — — 10,066 10,066 Prepayments and other assets (1) 4,410 — — — 4,410 4,410 Other non-current 10,243 — — — 10,243 10,243 Derivative assets — 2,212 12,771 — 14,983 14,983 Total carrying value $ 279,205 $ 2,212 $ 12,771 $ 99,954 $ 394,142 $ 394,142 Financial liabilities Financial liabilities at FVTPL Derivative designated as cash flow hedges (carried at fair value) Financial liabilities at amortized cost Total carrying value Total fair value Trade payables $ — $ — $ 19,703 $ 19,703 $ 19,703 Long term debt (includes current portion) (3) — — 89,900 89,900 89,900 Other employee obligations (4) — — 59,346 59,346 59,346 Provision and accrued expenses — — 28,826 28,826 28,826 Other liabilities (5) 11,388 — 2,447 13,835 13,835 Derivative liabilities 946 7,809 — 8,755 8,755 Total carrying value $ 12,334 $ 7,809 $ 200,222 $ 220,365 $ 220,365 Notes: (1) Excluding non-financial (2) Excluding non-financial (3) Excluding non-financial (4) Excluding non-financial (5) Excluding non-financial The carrying value and fair value of financial instruments by class as at March 31, 2017 are as follows: Financial assets Loans and receivables Financial assets at FVTPL Derivative designated as cash flow hedges (carried at fair value) Available for sale Total carrying value Total fair value Cash and cash equivalents $ 69,803 $ — $ — $ — $ 69,803 $ 69,803 Investment in fixed deposits 24,673 — — — 24,673 24,673 Investments in marketable securities and mutual funds — — — 87,652 87,652 87,652 Investment in FMPs — 96 — — 96 96 Trade receivables 60,423 — — — 60,423 60,423 Unbilled revenue 48,915 — — — 48,915 48,915 Funds held for clients 9,135 — — — 9,135 9,135 Prepayments and other assets (1) 4,262 — — — 4,262 4,262 Other non-current 10,791 — — — 10,791 10,791 Derivative assets — 5,041 36,941 — 41,982 41,982 Total carrying value $ 228,002 $ 5,137 $ 36,941 $ 87,652 $ 357,732 $ 357,732 Financial liabilities Financial liabilities at FVTPL Derivative designated as cash flow hedges (carried at fair value) Financial liabilities at amortized cost Total carrying value Total fair value Trade payables $ — $ — $ 14,239 $ 14,239 $ 14,239 Long term debt (includes current portion) (3) — — 118,000 118,000 118,000 Other employee obligations (4) — — 46,701 46,701 46,701 Provision and accrued expenses — — 27,217 27,217 27,217 Other liabilities (5) 19,678 — 1,086 20,764 20,764 Derivative liabilities 26 4,757 — 4,783 4,783 Total carrying value $ 19,704 $ 4,757 $ 207,243 $ 231,704 $ 231,704 Notes: (1) Excluding non-financial (2) Excluding non-financial (3) Excluding non-financial (4) Excluding non-financial (5) Excluding non-financial For the financial assets and liabilities subject to offsetting or similar arrangements, each agreement between the Company and the counterparty allows for net settlement of the relevant financial assets and liabilities when both elect to settle on a net basis. In the absence of such an election, financial assets and liabilities will be settled on a gross basis. Financial assets and liabilities subject to offsetting, enforceable master netting arrangements or similar agreements as at March 31, 2018 are as follows: Description of types of financial assets Gross amounts of recognized financial assets Gross amounts of recognized financial liabilities offset in the statement of financial position Net amounts of financial assets presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral received Derivative assets $ 14,983 $ — $ 14,983 $ (4,215 ) $ — $ 10,768 Total $ 14,983 $ — $ 14,983 $ (4,215 ) $ — $ 10,768 Description of types of financial liabilities Gross amounts of recognized financial liabilities Gross amounts of recognized financial assets offset in the statement of financial position Net amounts of financial liabilities presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral pledged Derivative liabilities $ 8,755 $ — $ 8,755 $ (4,215 ) $ — $ 4,540 Total $ 8,755 $ — $ 8,755 $ (4,215 ) $ — $ 4,540 Financial assets and liabilities subject to offsetting, enforceable master netting arrangements or similar agreements as at March 31, 2017 are as follows: Description of types of financial assets Gross amounts of recognized financial assets Gross amounts of recognized financial liabilities offset in the statement of financial position Net amounts of financial assets presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral received Derivative assets $ 41,982 $ — $ 41,982 $ (1,712 ) $ — $ 40,270 Total $ 41,982 $ — $ 41,982 $ (1,712 ) $ — $ 40,270 Description of types of financial liabilities Gross amounts of recognized financial liabilities Gross amounts of recognized financial assets offset in the statement of financial position Net amounts of financial liabilities presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral pledged Derivative liabilities $ 4,783 $ — $ 4,783 $ (1,712 ) $ — $ 3,071 Total $ 4,783 $ — $ 4,783 $ (1,712 ) $ — $ 3,071 Fair value hierarchy The following is the hierarchy for determining and disclosing the fair value of financial instruments by valuation technique: Level 1 — quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 — other techniques for which all inputs have a significant effect on the recorded fair value are observable, either directly or indirectly. Level 3 — techniques which use inputs that have a significant effect on the recorded fair value that are not based on observable market data. The fair value is estimated using the discounted cash flow approach and market rates of interest. The valuation technique involves assumptions and judgments regarding risk characteristics of the instruments, discount rates and future cash flows. The Company uses valuation techniques in measuring the fair value of financial instruments, where active market quotes are not available. In applying the valuation techniques, the Company makes maximum use of market inputs, and uses estimates and assumptions that are, as far as possible, consistent with observable data that market participants would use in pricing the instrument. Where applicable data is not observable, the Company uses its best estimate about the assumptions that market participants would make. These estimates may vary from the actual prices that would be achieved in an arm’s length transaction at the reporting date. The assets and liabilities measured at fair value on a recurring basis as at March 31, 2018 are as follows:- Fair value measurement at reporting date using Description March 31, 2018 Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Assets Financial assets at FVTPL Foreign exchange contracts $ 2,212 $ — $ 2,212 $ — Financial assets at fair value through other comprehensive income Foreign exchange contracts 11,709 — 11,709 — Interest rate swaps 1,062 — 1,062 — Investments in marketable securities and mutual funds 99,954 99,412 542 — Total assets $ 114,937 $ 99,412 $ 15,525 $ — Liabilities Financial liabilities at FVTPL Foreign exchange contracts $ 946 $ — $ 946 $ — Contingent consideration 11,388 — — 11,388 Financial liabilities at fair value through other comprehensive income Foreign exchange contracts 7,809 — 7,809 — Total liabilities $ 20,143 $ — $ 8,755 $ 11,388 The assets and liabilities measured at fair value on a recurring basis as at March 31, 2017 are as follows:- Fair value measurement at reporting date using Description March 31, 2017 Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Assets Financial assets at FVTPL Foreign exchange contracts $ 5,041 $ — $ 5,041 $ — Investment in FMPs 96 96 — — Financial assets at fair value through other comprehensive income Foreign exchange contracts 36,733 — 36,733 — Interest rate swaps 208 — 208 — Investments in marketable securities and mutual funds 87,652 87,223 429 — Total assets $ 129,730 $ 87,319 $ 42,411 $ — Liabilities Financial liabilities at FVTPL Foreign exchange contracts $ 26 $ — $ 26 $ — Contingent consideration 19,678 — — 19,678 Financial liabilities at fair value through other comprehensive income Foreign exchange contracts 4,136 — 4,136 — Interest rate swaps 621 — 621 — Total liabilities $ 24,461 $ — $ 4,783 $ 19,678 Description of significant unobservable inputs to Level 3 valuation The fair value of the contingent consideration liability was estimated using a probability weighted method and achievement of revenue target with a discount rate of 2.5%. One percentage point change in the unobservable inputs used in fair valuation of the contingent consideration does not have a significant impact on its value. The fair value is estimated using discounted cash flow approach which involves assumptions and judgments regarding risk characteristics of the instruments, discount rates, future cash flows, foreign exchange spot, forward premium rates and market rates of interest. The movement in contingent consideration categorized under Level 3 fair value measurement is given below: For the year ended March 31, 2018 March 31, 2017 Balance at the beginning of the year $ 19,678 $ — Additions — 19,934 Payouts (7,000 ) — Gain recognized in the consolidated statement of income (1,553 ) (279 ) Finance expense recognized in the consolidated statement of income 263 23 Balance at the end of the year 11,388 19,678 During the years ended March 31, 2018 and 2017, there were no transfers between Level 1 and Level 2 fair value measurements, and no transfers into and out of Level 3 fair value measurements. Fair value on a non-recurring The non-recurring Derivative financial instruments The primary risks managed by using derivative instruments are foreign currency exchange risk and interest rate risk. Forward and option contracts up to 24 months on various foreign currencies are entered into to manage the foreign currency exchange rate risk on forecasted revenue denominated in foreign currencies and monetary assets and liabilities held in non-functional The following table presents the notional values of outstanding foreign exchange forward contracts, foreign exchange option contracts and interest rate swap contracts: As at March 31, 2018 March 31, 2017 Forward contracts (Sell) In US dollars $ 242,418 $ 241,673 In United Kingdom Pound Sterling 132,591 126,441 In Euro 23,883 14,769 In Australian dollars 48,147 43,474 Others 2,332 3,511 $ 449,371 $ 429,868 Option contracts (Sell) In US dollars $ 107,629 $ 84,490 In United Kingdom Pound Sterling 116,401 94,094 In Euro 21,483 14,494 In Australian dollars 28,828 19,412 Others 927 1,978 $ 275,268 $ 214,468 Interest Rate Swap contracts In US dollars 89,900 118,000 The amount of gain/ (loss) reclassified from other comprehensive income into consolidated statement of income in respective line items for the years ended March 31, 2018, 2017 and 2016 are as follows: Year ended March 31, 2018 2017 2016 Revenue $ 11,231 $ 7,952 $ 7,941 Foreign exchange gain, net 15,766 16,896 6,281 Finance expense (561 ) (71 ) — Income tax related to amounts reclassified into consolidated statement of income (9,965 ) (8,998 ) (5,230 ) Total $ 16,471 $ 15,779 $ 8,992 As at March 31, 2018, a loss amounting to $1,015 on account of cash flow hedges in relation to forward and option contracts entered is expected to be reclassified from other comprehensive income into consolidated statement of income over a period of 24 months and a gain amounting to $995 on account of cash flow hedges in relation to interest rate swaps is expected to be reclassified from other comprehensive income into consolidated statement of income over a period of 48 months. Due to the discontinuation of cash flow hedge accounting on account of non-occurrence Financial risk management Financial risk factors The Company’s activities expose it to a variety of financial risks: market risk, interest risk, credit risk and liquidity risk. The Company’s primary focus is to foresee the unpredictability of financial markets and seek to minimize potential adverse effects on its financial performance. The primary market risk to the Company is foreign exchange risk. The Company uses derivative financial instruments to mitigate foreign exchange related risk exposures. The Company’s exposure to credit risk is influenced mainly by the individual characteristic of each customer and the concentration of risk from the top few customers. The demographics of the customer including the default risk of the industry and country in which the customer operates also has an influence on credit risk assessment. The Company does not enter into or trade financial instruments, including derivative financial instruments, for speculative purposes. Risk management procedures The Company manages market risk through treasury operations. Senior management and Board of Directors approve the Company’s treasury operations’ objectives and policies. The activities of treasury operations include management of cash resources, implementation of hedging strategies for foreign currency exposures, implementation of borrowing strategies and monitoring compliance with market risk limits and policies. The Company’s foreign exchange committee, comprising the Chairman of the Board, Group Chief Executive Officer and Group Chief Financial Officer, is the approving authority for all hedging transactions. Components of market risk Exchange rate or currency risk: The Company’s exposure to market risk arises principally from exchange rate risk. Although substantially all of revenue is denominated in pound sterling and US dollars, a significant portion of expenses for the year ended March 31, 2018 (net of payments to repair centers made as part of the Company’s WNS Auto Claims BPM segment) were incurred and paid in Indian rupees. The exchange rates among the Indian rupee, the pound sterling and the US dollar have changed substantially in recent years and may fluctuate substantially in the future. The Company hedges a portion of forecasted external and inter-company revenue denominated in foreign currencies with forward contracts and options. Based upon the Company’s level of operations for the year ended March 31, 2018, a sensitivity analysis shows that a 10% appreciation or depreciation in the pound sterling against the US dollar would have increased or decreased, respectively, the Company’s revenue for the year ended March 31, 2018 by approximately $24,107. Similarly, a 10% appreciation or depreciation in the Indian rupee against the US dollar would have increased or decreased, respectively, the Company’s expenses incurred and paid in Indian rupee for the year ended March 31, 2018 by approximately $27,282. The foreign currency risk from non-derivative As at March 31, 2018 US Dollar Pound Sterling Indian Rupees Australian Dollar Euro Other currencies Total Cash and cash equivalents $ 399 4,735 — 2,991 339 610 9,074 Trade receivables 100,002 46,658 3,850 24,686 7,289 2,525 185,010 Unbilled revenue 7,178 3,209 — 643 6,230 858 18,118 Prepayments and other current assets 428 188 10 29 63 11 729 Other non-current 3 — — — — 16 19 Trade payables (27,613 ) (64,070 ) (6,989 ) (16,093 ) (1,429 ) (19 ) (116,213 ) Provisions and accrued expenses (2,314 ) (291 ) (205 ) — (154 ) (19 ) (2,983 ) Pension and other employee obligations (134 ) — — — (12 ) (306 ) (452 ) Other liabilities (7 ) (4 ) — — — — (11 ) Net assets/ (liabilities) $ 77,942 (9,575 ) (3,334 ) 12,256 12,325 3,676 93,291 The foreign currency risk from non-derivative As at March 31, 2017 US Dollar Pound Sterling Indian Rupees Australian Dollar Euro Other currencies Total Cash and cash equivalents $ 599 253 — 2,606 1,323 35 4,816 Trade receivables 98,713 53,668 2,996 23,373 5,370 3,192 187,312 Unbilled revenue 4,656 1,241 3,062 3,205 494 12,658 Prepayments and other current assets 428 130 3 66 30 14 671 Other non-current 3 — — — — 16 19 Trade payables (40,600 ) (71,039 ) (3,986 ) (19,205 ) (1,140 ) (312 ) (136,282 ) Provisions and accrued expenses (1,706 ) (504 ) (105 ) (128 ) (68 ) (208 ) (2,719 ) Pension and other employee obligations (56 ) — — — (31 ) (165 ) (252 ) Other liabilities (5 ) (2 ) — — — 14 7 Net assets/ (liabilities) $ 62,032 (16,253 ) (1,092 ) 9,774 8,689 3,080 66,230 Other currencies includes mainly currencies such as Swiss Franc (CHF), Singapore Dollar (SGD), Philippine Peso (PHP), Canadian Dollar (CAD), Polish Zloty (PLN), Sri Lankan Rupee (LKR), Romanian Leu (RON), South African Rand (ZAR) and New Zealand Dollar (NZD). As at March 31, 2018, every 5% appreciation or depreciation of the respective foreign currencies compared to the functional currency of the Company would impact the Company’s profit before tax from operating activities by approximately $3,751. Interest rate risk: The Company’s exposure to interest rate risk arises from borrowings which have a floating rate of interest, which is linked to the US dollar LIBOR. The risk is managed by the Company by maintaining an appropriate mix between fixed and floating rate borrowings and by the use of interest rate swap contracts. The costs of floating rate borrowings may be affected by the fluctuations in the interest rates. In connection with the term loan facilities entered in fiscal 2017, the Company entered into interest rate swap agreements with the banks in fiscal 2017. These swap agreements effectively convert the term loans from variable US dollar LIBOR interest rates to fixed rates, thereby managing the Company’s exposure to changes in market interest rates under the term loans. The outstanding swap agreements as at March 31, 2018 aggregated $89,900. The Company monitors its positions and does not anticipate non-performance Credit risk: Credit risk arises from the possibility that customers may not be able to settle their obligations as agreed. Trade receivables are typically unsecured and are derived from revenue earned from customers primarily located in the United Kingdom and the United States. Credit risk is managed through periodical assessment of the financial reliability of customers, taking into account the financial condition, current economic trends, analysis of historical bad debts and ageing of trade receivables. The credit risk on marketable securities, FMPs, mutual funds, bank deposits and derivative financial instruments is limited because the counterparties are banks and mutual funds with high credit-ratings assigned by international credit-rating agencies. The following table gives details in respect of the percentage of revenue generated from the Company’s top customer and top five customers: Year Ended March 31, 2018 2017 2016 Revenue from top customer 6.8 % 9.0 % 10.9 % Revenue from top five customers 29.4 % 32.1 % 30.7 % Financial assets that are neither past due nor impaired Cash equivalents, bank deposits, marketable securities and investments in mutual funds, investment in FMPs, unbilled revenue and other assets, are neither past due nor impaired, except trade receivables as described below. Financial assets that are past due but not impaired There is no other class of financial assets that is past due but not impaired, except for trade receivables, which forms part of the class “Loans and receivables.” The Company’s credit period generally ranges from 30-60 age-wise As at March 31, 2018 March 31, 2017 Neither past due nor impaired $ 56,372 $ 45,939 Past due but not impaired Past due 0-30 9,578 8,260 Past due 31-60 2,738 2,544 Past due 61-90 834 1,174 Past due over 90 days 1,866 2,506 Past due and impaired 564 1,713 Total $ 71,952 $ 62,136 Allowances for doubtful trade receivables $ (564 ) $ (1,713 ) Trade receivables, net of allowances for doubtful receivables $ 71,388 $ 60,423 Liquidity risk: Liquidity risk is the risk that the Company will encounter difficulty in meeting the obligations associated with its financial liabilities that are settled by delivering cash or another financial asset. The Company’s approach to managing liquidity is to ensure, as far as possible, that it will always have sufficient liquidity to meet its liabilities when due, under normal and stressed conditions, without incurring unacceptable losses or risking damage to the reputation. Typically the Company ensures that it has sufficient cash on demand to meet expected operational expenses and service financial obligations. In addition, the Company has concluded arrangements with well reputed banks and has unused lines of credit of $78,290 as of March 31, 2018 that could be drawn upon should there be a need. The contractual maturities of financial liabilities are as follows: As at March 31, 2018 Less than 1 Year 1-2 years 2-5 years Total Long term debt (includes current portion) (1) $ 28,100 $ 28,200 $ 33,600 $ 89,900 Trade payables 19,703 — — 19,703 Provision and accrued expenses 28,826 — — 28,826 Other liabilities 10,680 3,154 — 13,834 Other employee obligations 59,347 — — 59,347 Derivative financial instruments 6,466 2,289 — 8,755 Total (2) $ 153,122 $ 33,643 $ 33,600 $ 220,365 Notes: (1) Before netting off debt issuance cost of $769. (2) Non-financial As at March 31, 2017 Less than 1 Year 1-2 years 2-5 years Total Long term debt (includes current portion) (1) $ 28,100 $ 28,100 $ 61,800 $ 118,000 Trade payables 14,239 — — 14,239 Provision and accrued expenses 27,217 — — 27,217 Other liabilities 9,338 8,195 3,231 20,764 Other employee obligations 46,701 — — 46,701 Derivative financial instruments 3,947 836 — 4,783 Total (2) $ 129,542 $ 37,131 $ 65,031 $ 231,704 Notes: (1) Before netting off debt issuance cost of $1,257. (2) Non-financial The balanced view of liquidity and financial indebtedness is stated in the table below. This calculation of the net cash position is used by the management: As at March 31, 2018 March 31, 2017 Cash and cash equivalents $ 99,829 $ 69,803 Investments 121,502 112,421 Long term debt (includes current portion) (1) (89,900 ) (118,000 ) Net cash position $ 131,431 $ 64,224 Note: (1) Before netting off debt issuance cost of $769 and $1,257 as at March 31, 2018 and March 31, 2017, respectively.

Pension and other employee obli

Pension and other employee obligations	12 Months Ended
	Mar. 31, 2018
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Pension and other employee obligations	14. Pension and other employee obligations Pension and other employee obligations consist of the following: As at March 31, 2018 March 31, 2017 Current: Salaries and bonus $ 59,346 $ 46,701 Pension 1,189 770 Withholding taxes on salary and statutory payables 4,082 5,462 Total $ 64,617 $ 52,933 Non-current: Pension and other obligations $ 9,621 $ 10,680 Total $ 9,621 $ 10,680 Employee benefit costs consist of the following: Year ended March 31, 2018 2017 2016 Salaries and bonus $ 405,665 $ 307,378 $ 272,017 Employee benefit plans: Defined contribution plan 11,684 10,265 7,458 Defined benefit plan 3,042 2,639 2,184 Share-based compensation expense (Refer Note 22) 30,565 23,036 17,919 Total $ 450,956 $ 343,318 $ 299,578 Employee benefit costs is recognized in the following line items in the consolidated statement of income: Year ended March 31, 2018 2017 2016 Cost of revenue $ 329,289 $ 249,701 $ 217,098 Selling and marketing expenses 31,373 24,717 22,336 General and administrative expenses 90,294 68,900 60,144 Total $ 450,956 $ 343,318 $ 299,578 Defined contribution plan The Company’s contributions to defined contribution plans are as follows: Year ended March 31, 2018 2017 2016 India $ 8,123 $ 7,587 $ 5,173 Philippines 127 106 83 South Africa 860 715 617 Sri Lanka 625 661 612 United Kingdom 670 780 681 United States 1,279 416 292 Total 11,684 10,265 7,458 Defined benefit plan The net periodic cost recognized by the Company in respect of gratuity payments under the Company’s gratuity plans covering eligible employees of the Company in India, the Philippines and Sri Lanka is as follows: Year ended March 31, 2018 2017 2016 Service cost $ 1,917 $ 2,188 $ 1,765 Past service cost 538 — — Interest on the net defined benefit liability 587 451 419 Net gratuity cost $ 3,042 $ 2,639 $ 2,184 As at March 2018 March 2017 Change in projected benefit obligations Obligation at beginning of the year $ 11,776 $ 8,450 Foreign currency translation (118 ) (30 ) Service cost 1,917 2,188 Past service cost 538 — Interest cost 657 513 Business combinations — 95 Benefits paid (1,160 ) (1,283 ) Actuarial (gain)/loss From changes in demographic assumptions 62 463 From changes in financial assumptions (3,428 ) (126 ) From actual experience compared to assumptions 857 1,506 Benefit obligation at end of the year $ 11,101 $ 11,776 Change in plan assets Plan assets at beginning of the year $ 976 $ 849 Foreign currency translation (5 ) 22 Expected return on plan assets 70 62 Actuarial (loss) /gain (23 ) 39 Actual contributions 1,104 1,148 Benefits paid (1,081 ) (1,144 ) Plan assets at end of the year $ 1,041 $ 976 Accrued pension liability Current $ 1,189 $ 770 Non-current 8,871 10,030 Net amount recognized $ 10,060 $ 10,800 Present value of funded defined benefit obligation $ 10,418 $ 8,766 Fair value of plan assets (1,041 ) (976 ) 9,377 7,790 Present value of unfunded defined benefit obligation $ 683 $ 3,010 Weighted average duration of defined benefit obligation (both funded and unfunded) 4.8 years 8.3 years Net amount recognized relating to the Company’s India plan, Philippines plan and Sri Lanka plan was $9,402, $36 and $622 as at March 31, 2018 and $7,973, $2,341 and $486 as at March 31, 2017, respectively. In March 2018, the Government of India amended the Payment of Gratuity Act, 1972 to increase the maximum limit of lump-sum The assumptions used in accounting for the gratuity plans are as follows: Year ended March 31, 2018 2017 2016 Discount rate: India 6.6% to 7.3 % 7.05 % 7.35 % Philippines 3.1 % 5.45 % 4.75 % Sri Lanka 10.0 % 12.8 % 12.30 % Rate of increase in compensation level 7% to 10 % 7% to 15 % 6% to 8 % Expected rate of return on plan assets 7.3 % 7.05 % 7.35 % The Company evaluates these assumptions annually based on its long-term plans of growth and industry standards. The discount rates are based on current market yields on government securities adjusted for a suitable risk premium to reflect the additional risk for high quality corporate bonds. As at March 31, 2018, for each of the Company’s defined benefit plans, the sensitivity of the defined benefit obligation to a change in each significant actuarial assumption is as follows: India Philippines Sri Lanka Discount rate: Increase in discount rate by 1% (7.3 )% (1.4 )% (3.4 )% Decrease in discount rate by 1% 0.7 % 1.5 % 0.5 % Rate of increase in compensation level: Increase in salary escalation rate by 1% 3.6 % 1.0 % 1.5 % Decrease in salary escalation rate by 1% (3.5 )% (0.9 )% (1.5 )% Each sensitivity amount is calculated assuming that all other assumptions are held constant. The Company is not able to predict the extent of likely future changes in these assumptions, but based on past experience, the discount rate for each plan could change by up to 1% within a 12 month period. As at March 31, 2018, $4 and $1,037 ($4 and $973 as at March 31, 2017) of the fund assets are invested with LIC and ALICPL, respectively. Of the funds invested with LIC, approximately 40% and 60% of the funds are invested in unquoted government securities and money market instruments, respectively. Of the funds invested with ALICPL, approximately 57% and 43% are invested in unquoted government securities and money market instruments, respectively. Since the Company’s plan assets are managed by third party fund administrators, the contributions made by the Company are pooled with the corpus of the funds managed by such fund administrators and invested in accordance with regulatory guidelines. The Company’s funding policy is to contribute to the Plan amounts necessary on an actuarial basis to, at a minimum, satisfy the minimum funding requirements. Additional discretionary contributions above the minimum funding requirement can be made and are generally based on adjustment for any over or under funding. The expected benefits are based on the same assumptions used to measure the Company’s defined benefit obligations as at March 31, 2018. The Company expects to contribute $1,962 for the year ending March 31, 2019. The maturity analysis of the Company’s defined benefit payments is as follows: Amount 2019 $ 2,230 2020 2,194 2021 2,179 2022 2,245 2023 2,370 Thereafter 9,260 $ 20,478

Provisions and accrued expenses

Provisions and accrued expenses	12 Months Ended
	Mar. 31, 2018
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Provisions and accrued expenses	15. Provisions and accrued expenses Provisions and accrued expenses consist of the following: As at March 31, 2018 March 31, 2017 Accrued expenses 28,826 27,217 Total $ 28,826 $ 27,217

Deferred revenue

Deferred revenue	12 Months Ended
	Mar. 31, 2018
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Deferred revenue	16. Deferred revenue Deferred revenue consists of the following: As at March 31, 2018 March 31, 2017 Current: Payments in advance of services $ 557 $ 717 Advance billings 2,104 4,014 Others 247 747 Total $ 2,908 $ 5,478 Non-current: Payments in advance of services $ 550 $ 359 Advance billings 2 — Others 19 19 Total $ 571 $ 378

Other liabilities

Other liabilities	12 Months Ended
	Mar. 31, 2018
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Other liabilities	17. Other liabilities Other liabilities consist of the following: As at March 31, 2018 March 31, 2017 Current: Withholding taxes and value added tax payables $ 5,117 $ 5,356 Contingent consideration (Refer note 4(a), 4(b) and 4(c)) 8,233 8,252 Deferred rent 800 677 Other liabilities 1,589 1,730 Total $ 15,739 $ 16,015 Non-current: Deferred rent $ 6,544 $ 5,292 Contingent consideration (Refer note 4(a), 4(b) and 4(c)) 3,155 11,426 Other liabilities 1,963 1,751 Total $ 11,662 $ 18,469

Share capital

Share capital	12 Months Ended
	Mar. 31, 2018
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Share capital	18. Share capital As at March 31, 2018, the authorized share capital was £6,100 divided into 60,000,000 ordinary shares of 10 pence each and 1,000,000 preferred shares of 10 pence each. The Company had 50,434,080 ordinary shares (excluding 4,400,000 treasury shares) outstanding as at March 31, 2018. There were no preferred shares outstanding as at March 31, 2018. As at March 31, 2017, the authorized share capital was £6,100 divided into 60,000,000 ordinary shares of 10 pence each and 1,000,000 preferred shares of 10 pence each. The Company had 50,012,559 ordinary shares (excluding 3,300,000 treasury shares) outstanding as at March 31, 2017. There were no preferred shares outstanding as at March 31, 2017. Treasury shares On March 16, 2016, the Company’s shareholders authorized a share repurchase program for the repurchase of up to 3,300,000 of the Company’s American Depository Shares (“ADSs”) each representing one ordinary share, par value 10 pence per share of the Company, at a price range of $10 to $50 per ADS. Pursuant to the terms of the repurchase program, the Company’s ADSs may be purchased in the open market from time to time for 36 months from March 16, 2016, the date of shareholders’ approval. The Company was not obligated under the repurchase program to repurchase a specific number of ADSs, and the repurchase program could be suspended at any time at the Company’s discretion. During the year ended March 31, 2017, the Company purchased 2,200,000 ADSs in the open market for a total consideration of $64,224 (including transaction costs of $33 for share repurchase of 2,200,000 ADSs, $111 paid towards cancellation fees for ADSs in relation to share repurchase of 2,200,000 ADSs which was completed during the year ended March 31, 2017, and $55 paid towards cancellation fees for ADSs in relation to share repurchase of 1,100,000 ADSs, which was completed during the year ended March 31, 2016). The shares underlying these purchased ADSs are recorded as treasury shares. During the year ended March 31, 2018, the Company purchased the balance 1,100,000 ADSs in the open market for a total consideration of $39,546 (including transaction costs of $17) and completed the share repurchase program. In March 2018, the shareholders of the Company authorized the repurchase of up to 3,300,000 of the Company’s ADSs, at a price range of $10 to $100 per ADS. Pursuant to the terms of the repurchase program, the Company’s ADSs may be purchased in the open market from time to time for 36 months from March 30, 2018, the date of shareholders’ approval. The Company is not obligated under the repurchase program to repurchase a specific number of ADSs, and the repurchase program could be suspended at any time at the Company’s discretion. The Company intends to fund the repurchase with cash on hand.

Expenses by nature

Expenses by nature	12 Months Ended
	Mar. 31, 2018
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Expenses by nature	19. Expenses by nature Expenses by nature consist of the following: Year ended March 31, 2018 2017 2016 Employee cost $ 450,956 $ 343,318 $ 299,578 Repair payments 16,970 24,102 31,170 Facilities cost 89,037 75,383 67,689 Depreciation 19,954 16,903 15,435 Legal and professional expenses 22,972 15,902 13,227 Travel expenses 23,748 18,563 17,972 Others 38,886 33,526 30,035 Total cost of revenue, selling and marketing and general and administrative expenses $ 662,523 $ 527,697 $ 475,106

Finance expense

Finance expense	12 Months Ended
	Mar. 31, 2018
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Finance expense	20. Finance expense Finance expense consists of the following: Year ended March 31, 2018 2017 2016 Interest expense $ 3,215 $ 424 $ 265 Interest rate swaps 561 71 — Debt issue cost 488 52 13 Total $ 4,264 $ 547 $ 278

Other income, net

Other income, net	12 Months Ended
	Mar. 31, 2018
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Other income, net	21. Other income, net Other income, net consists of the following: Year ended March 31, 2018 2017 2016 Interest income $ 3,693 $ 2,083 $ 1,197 Dividend income 3,570 4,131 5,039 Net gain arising on financial assets designated as FVTPL 3 6 41 Others, net 3,964 2,469 2,217 Total $ 11,230 $ 8,689 $ 8,494

Share-based payments

Share-based payments	12 Months Ended
	Mar. 31, 2018
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Share-based payments	22. Share-based payments The Company has three share-based incentive plans: the 2002 Stock Incentive Plan adopted on July 1, 2002 (which has expired), the 2006 Incentive Award Plan adopted on June 1, 2006, as amended and restated in February 2009, September 2011 and September 2013 (which has expired), and the 2016 Incentive Award Plan effective from September 27, 2016 (collectively referred to as the “Plans”). All the Plans are equity-settled. Under the Plans, share-based options and RSUs may be granted to eligible participants. Options and RSUs are generally granted for a term of ten years and have a graded vesting period of up to four years. The Company settles employee share-based options and RSU exercises with newly issued ordinary shares. As at March 31, 2018, the Company had 2,515,803 ordinary shares available for future grants. Share-based compensation expense during the years ended March 31, 2018, 2017 and 2016 are as follows: Year ended March 31, 2018 2017 2016 Share-based compensation expense recorded in $ $ $ Cost of revenue 3,770 2,765 1,923 Selling and marketing expenses 2,557 1,723 1,370 General and administrative expenses 24,238 18,548 14,626 Total share-based compensation expense $ 30,565 $ 23,036 $ 17,919 Upon exercise of share options and RSUs, the Company issued 1,521,521, 906,255 and 455,642 shares during the years ended March 31, 2018, 2017 and 2016, respectively. Share-based options Movements in the number of options outstanding under the 2006 Incentive Award Plan and their related weighted average exercise prices are as follow: Shares Weighted average exercise price Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 739,618 $ 23.34 0.54 $ 5,419 Exercised (425,941 ) 10.52 Lapsed (196,498 ) 13.44 Outstanding as at March 31, 2017 117,179 $ 27.25 0.10 $ 163 Exercised (48,227 ) 7.63 Lapsed (68,952 ) 7.87 Outstanding as at March 31, 2018 — — — — Options exercisable — $ — — $ — The aggregate intrinsic value of options exercised during the year ended March 31, 2018, 2017 and 2016 was $180, $2,697 and $856, respectively. The total grant date fair value of options vested during the year ended March 31, 2018, 2017 and 2016 was $Nil for each year. Total cash received as a result of options exercised during the year ended March 31, 2018, 2017 and 2016 was $1,347, $8,941 and $1,302, respectively. The fair value of options granted is estimated on the date of grant using the Black-Scholes-Merton option-pricing model. No options were granted during the years ended March 31, 2018, 2017 and 2016. The weighted average share price of options exercised during the year ended March 31, 2018, 2017 and 2016 was $30.44, $27.46 and $28.19, respectively. As no options were outstanding at March 31, 2018, there was no exercise price for these options (March 31, 2017: $15.68 to $29.21) and their weighted average remaining contractual term was zero years (March 31, 2017: 0.10 years) Restricted Share Units The 2006 Incentive Award Plan and the 2016 Incentive Award Plan also allow for grant of RSUs. Each RSU represents the right to receive one ordinary share and vests over a period of up to three years. (i) Movements in the number of RSUs dependent on non-market Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 1,448,312 $ 19.25 7.78 $ 44,376 Granted 516,264 30.26 Exercised (343,623 ) 20.18 Forfeited (47,707 ) 25.50 Lapsed — — Outstanding as at March 31, 2017 1,573,246 $ 22.47 7.50 $ 45,011 Granted 497,689 30.85 Exercised (961,111 ) 21.45 Forfeited (34,775 ) 29.07 Lapsed (2,216 ) 23.47 Outstanding as at March 31, 2018 1,072,833 $ 27.05 7.75 $ 48,632 RSUs exercisable 309,312 $ 20.90 5.94 $ 14,021 The fair value of RSUs is generally the market price of the Company’s shares on the date of grant. As at March 31, 2018, there was $6,893 of unrecognized compensation cost related to unvested RSUs. This amount is expected to be recognized over a weighted average period of 2.7 years. To the extent the actual forfeiture rate is different than what the Company has anticipated, share-based compensation expense related to these RSUs will be different from the Company’s expectations. The weighted average grant date fair value of RSUs granted during the year ended March 31, 2018, 2017 and 2016 was $30.85, $30.26, and $25.16 per ADS, respectively. The aggregate intrinsic value of RSUs exercised during the year ended March 31, 2018, 2017 and 2016 was $34,339, $9,991 and $10,294, respectively. The total grant date fair value of RSUs vested during the year ended March 31, 2018, 2017 and 2016 was $16,931, $14,631 and $6,824, respectively. The weighted average share price of RSU exercised during the year ended March 31, 2018, 2017 and 2016 was $35.73, $29.08 and $28.52, respectively. (ii) The 2006 Incentive Award Plan and the 2016 Incentive Award Plan also allow for grant of RSUs based on the market price of the Company’s shares achieving a specified target over a period of time. The fair value of market-based share awards is determined using Monte-Carlo simulation. Movements in the number of RSUs dependent on market performance condition outstanding under the 2006 Incentive Award Plan and the 2016 Incentive Award Plan and their related weighted average fair values are as follows: Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 129,590 $ 4.44 8.53 $ 3,971 Granted 74,400 12.56 Exercised — — Forfeited — — Lapsed — — Outstanding as at March 31, 2017 203,990 $ 13.21 8.10 $ 5,836 Granted — Exercised — Forfeited — Lapsed — Outstanding as at March 31, 2018 203,990 13.21 7.10 $ 9,247 RSUs exercisable — $ — — $ — On March 15, 2017, the Company modified the vesting period in respect of the RSUs as below: a. for RSUs granted in April 2014, the vesting date has been extended to the fifth anniversary of the grant date (i.e. April 2019) b. for RSUs granted in April 2015, the vesting date has been extended to the fourth anniversary of the grant date (i.e. April 2019) c. for RSUs granted in April 2016, the vesting date has been extended to the fourth anniversary of the grant date (i.e. April 2020) Subsequent vesting of RSUs for each of the remaining years would be subject to continued employment. The incremental fair value was determined using Monte-Carlo simulation by reference to the difference between fair value of original RSUs as of modification date and the fair value of modified RSUs as of modification date. The additional cost as a result of such modification in respect of modified share awards amounted to $1,185. The additional cost is spread over the period from the modification date until the vesting date of the modified award, which differ from the vesting date of the original award. The incremental cost recognized in the current year (March 31, 2017: $24) in respect of such modified share awards amounted to $540. As at March 31, 2018, there was $963 of unrecognized compensation cost related to unvested market based RSUs. This amount is expected to be recognized over a weighted average period of 1.3 years. The weighted average grant date fair value of the RSUs granted during the years ended March 31, 2018, 2017 and 2016 was Nil, $12.56 and $6.37 per ADS, respectively. (iii) RSUs related to Total Shareholder’s Return (“TSR”) During the year ended March 31, 2018, the Company issued 248,655 RSUs to certain employees. The conditions for the vesting of these RSUs are linked to the TSR of the Company in addition to the condition of continued employment with the Company through the applicable vesting period. The performance of these RSUs shall be assessed based on the TSR of the custom peer group (based on percentile rank) and the industry index (based on outperformance rank). The RSUs granted with the TSR condition shall vest on the third anniversary of the grant date, subject to the participant’s continued employment with the Company through the applicable vesting date and achievement of the specified conditions of stock performance and TSR parameters. The fair value of these RSUs is determined using Monte-Carlo simulation. The grant date fair value was determined at $36.52. The stock compensation expense charged during the year ended March 31, 2018 was $1,368. As at March 31, 2018, there was $3,585 of unrecognized compensation cost related to these RSUs. Movements in the number of RSUs linked to the TSR condition outstanding under the 2016 Incentive Award Plan and their related weighted average fair values are as follows: Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2017 — $ — — $ — Granted 248,655 36.52 Exercised — Forfeited — Lapsed — Outstanding as at March 31, 2018 248,655 36.52 9.08 11,272 RSUs exercisable — $ — — $ — Performance share units The 2006 Incentive Award Plan and 2016 Incentive Award Plan also allow for grant of performance share units (“PSUs”). Each PSU represents the right to receive one ordinary share-based on the Company’s performance against specified non-market Movements in the number of PSUs outstanding under the 2006 Incentive Award Plan and the 2016 Incentive Award Plan and their related weighted average fair values are as follow: Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 951,588 $ 17.83 7.77 $ 29,157 Granted 422,062 31.12 Exercised (141,741 ) 14.11 Forfeited (47,057 ) 26.27 Outstanding as at March 31, 2017 1,184,852 $ 21.00 7.36 $ 33,899 Granted 400,463 30.35 Exercised (506,660 ) 16.79 Forfeited (18,681 ) 29.38 Outstanding as at March 31, 2018 1,059,975 26.36 7.51 48,048 PSUs exercisable 194,629 $ 18.14 5.86 $ 8,823 The fair value of PSUs is generally the market price of the Company’s shares on the date of grant, and assumes that performance targets will be achieved. As at March 31, 2018, there was $8,634 of unrecognized compensation cost related to unvested PSUs, net of forfeitures. This amount is expected to be recognized over a weighted average period of 2.2 years. Over the performance period, the number of shares that will be issued will be adjusted upward or downward based upon the probability of achievement of the performance targets. The ultimate number of shares issued and the related compensation cost recognized as expense will be based on a comparison of the final performance metrics to the specified targets. The weighted average grant date fair value of PSUs granted during the years ended March 31, 2018, 2017 and 2016 was $30.35, $31.12, and $20.12 per ADS, respectively. The aggregate intrinsic value of PSUs exercised during the year ended March 31, 2018, 2017 and 2016 was $17,737, $4,237 and $532, respectively. The total grant date fair value of PSUs vested during the year ended March 31, 2018, 2017 and 2016 was $8,696, $6,280 and $Nil, respectively. The weighted average share price of PSU exercised during the year ended March 31, 2018, 2017 and 2016 was $35.01, $29.89 and $29.45, respectively. BBBEE program in South Africa During the year ended March 31, 2018, the Company’s South African subsidiary issued share appreciation rights to certain employees to be settled with the Company’s shares on the fourth anniversary of the grant date. As part of the settlement, the Company has granted 32,050 RSUs which shall vest on the fourth anniversary of the grant date, subject to such grantee’s continued employment with the Company through the applicable vesting date. The grant date fair value was estimated using a binomial lattice model. The total stock compensation expense in relation to these RSUs was $3,040 to be amortized over the vesting period of four years. The stock compensation expense charged during the year ended March 31, 2018 was $547.

Income taxes

Income taxes	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Income taxes	23. Income taxes The domestic and foreign source component of profit / (loss) before income taxes is as follows: Year ended March 31, 2018 2017 2016 Domestic $ (4,439 ) $ (5,342 ) $ (4,121 ) Foreign 106,306 60,635 85,181 Profit before income taxes $ 101,867 $ 55,293 $ 81,060 The Company’s provision for income taxes consists of the following: Year ended March 31, 2018 2017 2016 Current taxes Domestic taxes $ — $ — $ — Foreign taxes 24,494 25,785 19,615 24,494 25,785 19,615 Deferred taxes Domestic taxes — — — Foreign taxes (9,063 ) (8,255 ) 1,565 (9,063 ) (8,255 ) 1,565 Provision for income taxes $ 15,431 $ 17,530 $ 21,180 Domestic taxes are nil as the Company is subject to income tax in Jersey, Channel Islands at a rate of 0%. Foreign taxes are based on applicable tax rates in each subsidiary’s jurisdiction. On July 27, 2017, National Company Law Tribunal in India approved the scheme of amalgamation of Value Edge Research Services Limited (“Value Edge”) and WNS Global Services Private Limited (“WNS India”), pursuant to which, Value Edge was merged with and into WNS India. The merger resulted in the creation of a tax base of goodwill and certain other identifiable intangible assets in the financial statements of WNS India. WNS India is entitled to claim a tax benefit for amortization of goodwill and intangible assets in its future tax returns. The Company had previously recorded a deferred tax liability for the temporary differences between the tax base of identifiable intangible assets and its carrying amount in the Company’s consolidated financial statements upon the acquisition of Value Edge. As a result, the carrying value of such liability as at the effective date of the scheme of amalgamation, amounting to $1,686, was derecognized during the year ended March 31, 2018. The Company in fiscal 2012 started operations in delivery centers in Pune, Mumbai and Chennai, India registered under the Special Economic Zone (“SEZ”) scheme. These operations were eligible for a 100% income tax exemption until fiscal 2016 and are eligible for a 50% income tax exemption from fiscal 2017 to fiscal 2026. During fiscal 2015, the Company started operations in new delivery centers in Gurgaon and Pune, India registered under the SEZ scheme. These operations are eligible for a 100% income tax exemption until fiscal 2019, and a 50% income tax exemption from fiscal 2020 to fiscal 2029. During fiscal 2018, the Company started operations in new delivery centers in Pune and Gurgaon, India registered under the SEZ scheme that are eligible for a 100% income tax exemption until fiscal 2022, and a 50% income tax exemption from fiscal 2023 to fiscal 2032. The Government of India pursuant to the Indian Finance Act, 2011 has also levied a minimum alternate tax (“MAT”) on the book profits earned by the SEZ units at the prevailing rate which is currently 21.55%. The Company’s operations in Costa Rica are eligible for a 50% income tax exemption from fiscal 2018 to fiscal 2021. During fiscal 2013, the Company started operations in a delivery center in Techno Plaza II, Manila which was eligible for a tax exemption that expired in fiscal 2017. During fiscal 2016, the Company started operations in a new delivery center in the Philippines which is eligible for a tax exemption until fiscal 2020. During fiscal 2017, the Company opened two additional delivery centers in Iloilo and Alabang, Philippines which are eligible for a 100% tax exemption until fiscal 2021. During fiscal 2018, the Company opened an additional delivery center in Alabang, Philippines which is eligible for a 100% tax exemption until fiscal 2022. The Government of Sri Lanka has exempted the profits earned from export revenue from tax, which enables the Company’s Sri Lankan subsidiary to continue to claim a tax exemption until fiscal 2018 and would be taxed at 14% on net basis with effect from April 1, 2018. The “Tax Cuts and Jobs Act of 2017” was enacted on December 22, 2017 with an effective date of January 1, 2018. The reduction in the corporate tax rate from 35% to 21% will have an impact on the various current and deferred tax items recorded by the Company’s subsidiaries. At March 31, 2018, the Company has not completed its initial accounting for the tax effects of the Act. However, a reasonable estimate of the effects of such enactment has been made by recognizing a net one-time If the income tax exemption was not available, the additional income tax expense at the respective statutory rates in India, Sri Lanka and Philippines would have been approximately $9,368, $5,171 and $5,072 for the years ended March 31, 2018, 2017 and 2016, respectively. Such additional tax would have decreased the basic and diluted earnings per share for the year ended March 31, 2018 by $0.19 and $0.18, respectively ($0.10 and $0.10, respectively for the year ended March 31, 2017 and $0.10 and $0.09, respectively, for the year ended March 31, 2016). Income taxes recognized directly in equity are as follows: Year ended March 31, 2018 2017 2016 Current taxes: Excess tax deductions related to share-based payments (685 ) (270 ) (229 ) $ (685 ) $ (270 ) $ (229 ) Deferred taxes: Excess tax deductions related to share-based payments (1,135 ) 715 (688 ) $ (1,135 ) $ 715 $ (688 ) Total income tax recognized directly in equity $ (1,820 ) $ 445 $ (917 ) Income taxes recognized in other comprehensive income are as follows: Year ended March 31, 2018 2017 2016 Current taxes — — — Deferred taxes: Unrealized gain/(loss) on cash flow hedging derivatives (9,409 ) 6,921 (4,259 ) Total income tax recognized directly in other comprehensive income $ (9,409 ) $ 6,921 $ (4,259 ) The reconciliation of estimated income tax to provision for income taxes: Year ended March 31, 2018 2017 2016 Profit before income taxes $ 101,867 $ 55,293 $ 81,060 Income tax expense at tax rates applicable to individual entities 32,702 21,765 28,067 Effect of: Items not deductible for tax 221 455 771 Exempt income (11,250 ) (7,706 ) (6,845 ) Non tax deductible goodwill impairment — 4,335 — (Gain)/Loss in respect of which deferred tax (liability)/asset not recognized due to uncertainty and ineligibility to carry forward 324 (105 ) 259 Recognition of unutilized tax benefits / Unrecognized losses utilized — (1,220 ) (294 ) Temporary difference that will reverse during tax holiday period 22 1,580 30 Change in tax rate and law (5,685 ) 78 (152 ) Provision for uncertain tax position — (1,499 ) 2 State taxes 317 14 12 Due to acquisitions and merger (1,686 ) — — One time tax on undistributed earnings 266 — — Others, net 200 (167 ) (670 ) Provision for income taxes $ 15,431 $ 17,530 $ 21,180 Deferred taxes for the year ended March 31, 2018 arising from temporary differences and unused tax losses can be summarized below: Opening Balance Additions due to acquisition Recognized in statement of income Recognized in equity Recognized in/ Reclassified from other comprehensive income Foreign currency translation Closing balance Deferred tax assets: Property and equipment $ 5,648 $ (11 ) $ 1,623 $ — $ — $ 31 $ 7,291 Net operating loss carry forward 5,722 — (2,950 ) — — 107 2,879 Accruals deductible on actual payment 5,641 — 1,661 — — 122 7,424 Share-based compensation expense 12,264 — (702 ) 1,135 — 73 12,770 Minimum alternate tax 167 — 257 — — (4 ) 420 Others 975 — (661 ) — — 14 328 Total deferred tax assets $ 30,417 $ (11 ) $ (772 ) $ 1,135 $ — $ 343 $ 31,112 Deferred tax liabilities: Intangibles 21,123 6 (8,555 ) — — 88 12,662 Unrealized gain/(loss) on cash flow hedging and investments 12,294 — (1,280 ) — (9,409 ) 154 1,759 Others 1,113 — — — — (5 ) 1,108 Total deferred tax liabilities $ 34,530 $ 6 $ (9,835 ) $ — $ (9,409 ) $ 237 $ 15,529 Net deferred tax assets/(liabilities) $ (4,113 ) $ (17 ) $ 9,063 $ 1,135 $ 9,409 $ 106 $ 15,583 Deferred taxes for the year ended March 31, 2017 arising from temporary differences and unused tax losses can be summarized below: Opening balance Additions due to acquisition during the year Recognized in statement of income Recognized in equity Recognized in/ Reclassified from other comprehensive income Foreign currency translation Closing balance Deferred tax assets: Property and equipment $ 5,512 $ (873 ) $ 932 $ — $ — $ 77 $ 5,648 Net operating loss carry forward 3,684 — 2,026 — — 12 5,722 Accruals deductible on actual payment 5,352 70 (1 ) — — 220 5,641 Share-based compensation expense 11,008 — 1,781 (715 ) — 190 12,264 Minimum alternate tax 68 — 96 — — 3 167 Others 362 — 679 — — (66 ) 975 Total deferred tax assets $ 25,986 $ (803 ) $ 5,513 $ (715 ) $ — $ 436 $ 30,417 Deferred tax liabilities: Intangibles (712 ) 24,577 (2,769 ) — — 27 21,123 Unrealized gain/(loss) on cash flow hedging and investments 4,857 — 27 — 6,921 489 12,294 Others 1,108 — — — — 5 1,113 Total deferred tax liabilities $ 5,253 $ 24,577 $ (2,742 ) $ — $ 6,921 $ 521 $ 34,530 Net deferred tax assets/(liabilities) $ 20,733 $ (25,380 ) $ 8,255 $ (715 ) $ (6,921 ) $ (85 ) $ (4,113 ) Deferred taxes for the year ended March 31, 2016 arising from temporary differences and unused tax losses can be summarized below: Opening balance Additions due to acquisition during the year Recognized in statement of income Recognized in equity Recognized in/ Reclassified from other comprehensive income Foreign currency translation Closing balance Deferred tax assets: Property and equipment $ 6,538 $ — $ (724 ) $ — $ — $ (302 ) $ 5,512 Net operating loss carry forward 4,304 — (448 ) — — (172 ) 3,684 Accruals deductible on actual payment 4,201 — 1,443 — — (292 ) 5,352 Share-based compensation expense 6,110 — 4,480 688 — (270 ) 11,008 Minimum alternate tax 8,327 — (7,941 ) — — (318 ) 68 Others 1,444 — (1,179 ) — — 97 362 Total deferred tax assets $ 30,924 $ — $ (4,369 ) $ 688 $ — $ (1,257 ) $ 25,986 Deferred tax liabilities: Intangibles 2,045 837 (3,477 ) — — (118 ) (712 ) Unrealized gain/(loss) on cash flow hedging and investments 9,821 — (436 ) — (4,259 ) (269 ) 4,857 Others — — 1,108 — — — 1,108 Total deferred tax liabilities $ 11,866 $ 837 $ (2,804 ) $ — $ (4,259 ) $ (387 ) $ 5,253 Net deferred tax assets/(liabilities) $ 19,058 $ (837 ) $ (1,565 ) $ 688 $ 4,259 $ (870 ) $ 20,733 Deferred tax presented in the statement of financial position is as follows: As at March 31, 2018 March 31, 2017 Deferred tax assets 27,395 16,687 Deferred tax liabilities (11,812 ) (20,800 ) Net deferred tax assets $ 15,583 $ (4,113 ) There are unused tax losses amounting to $17,969 as at March 31, 2018 for which no deferred tax asset has been recognized as these losses relate to a tax jurisdiction where the group entity has had past losses and there is no conclusive evidence to support the view that sufficient taxable profit will be generated by such group entity in the future to offset such losses. The expiry dates of the tax benefit for these losses depend on the local tax laws of the jurisdiction and, if not utilized, would expire on various dates starting from financial year 2019 to 2023. Deferred income tax liabilities on earnings of Company’s subsidiaries have not been provided as such earnings are deemed to be permanently reinvested in the business and the Company is able to control the timing of the reversals of temporary differences associated with these investments. Accordingly, temporary difference on which deferred tax liability has not been recognized amounts to $494,571, $401,857 and $301,043 as at March 31, 2018, 2017 and 2016, respectively. From time to time, the Company receives orders of assessment from the Indian tax authorities assessing additional taxable income on the Company and/or its subsidiaries in connection with their review of their tax returns. The Company currently has orders of assessment outstanding for various years through fiscal 2014, which assess additional taxable income that could in the aggregate give rise to an estimated $43,583 (March 31, 2017: $37,085) in additional taxes, including interest of $17,234 (March 31, 2017: $13,744). These orders of assessment allege that the transfer prices the Company applied to certain of the international transactions between WNS Global and its other wholly-owned subsidiaries were not on arm’s length terms, disallow a tax holiday benefit claimed by the Company, deny the set off of brought forward business losses and unabsorbed depreciation and disallow certain expenses claimed as tax deductible by WNS Global. The Company has appealed against these orders of assessment before higher appellate authorities. In addition, the Company has orders of assessment pertaining to similar issues that have been decided in favor of the Company by appellate authorities, vacating the tax demands of $45,002 (March 31, 2017: $44,573) in additional taxes, including interest of $13,897 (March 31, 2017: $13,740). The income tax authorities have filed or may file appeals against these orders at higher appellate authorities. Uncertain tax positions are reflected at the amount likely to be paid to the taxation authorities. A liability is recognized in connection with each item that is not probable of being sustained on examination by taxing authority. The liability is measured using single best estimate of the most likely outcome for each position taken in the tax return. Thus, the provision would be the aggregate liability in connection with all uncertain tax positions. As of March 31, 2018, the Company has provided a tax reserve of $12,370 (March 31, 2017: $12,432) primarily on account of the Indian tax authorities’ denying the set off of brought forward business losses and unabsorbed depreciation. As at March 31, 2018, corporate tax returns for years ended March 31, 2015 and onward remain subject to examination by tax authorities in India. Based on the facts of these cases, the nature of the tax authorities’ disallowances and the orders from appellate authorities deciding similar issues in favor of the Company in respect of assessment orders for earlier fiscal years and after consultation with the Company’s external tax advisors, the Company believe these orders are unlikely to be sustained at the higher appellate authorities. The Company has deposited $13,416 (March 31, 2017: $12,031) of the disputed amounts with the tax authorities and may be required to deposit the remaining portion of the disputed amounts with the tax authorities pending final resolution of the respective matters. Others On March 21, 2009, the Company received an assessment order from the Indian service tax authority, demanding payment of $5,341 of service tax and related penalty for the period from March 1, 2003 to January 31, 2005. The assessment order alleges that service tax is payable in India on BPM services provided by the Company to clients based abroad as the export proceeds are repatriated outside India by the Company. In response to the appeal filed by the Company with appellate tribunal against the assessment order in April 2009, the appellate tribunal has remanded the matter back to lower tax authorities to be adjudicated afresh. After consultation with Indian tax advisors, the Company believes this order of assessment is more likely than not to be upheld in favor of the Company. The Company intends to continue to vigorously dispute the assessment.

Earnings per share

Earnings per share	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Earnings per share	24. Earnings per share The following table sets forth the computation of basic and diluted earnings per share: Year ended March 31, 2018 2017 2016 Numerator: Profit $ 86,436 $ 37,763 $ 59,880 Denominator: Basic weighted average ordinary shares outstanding 50,388,440 50,582,852 51,372,117 Dilutive impact of equivalent stock options and RSUs 2,527,160 2,357,456 2,267,553 Diluted weighted average ordinary shares outstanding 52,915,600 52,940,308 53,639,670 The computation of earnings per ordinary share (“EPS”) was determined by dividing profit by the weighted average ordinary shares outstanding during the respective periods. The Company excluded from the calculation of diluted EPS options and RSUs to purchase 27,350, 5,200 and 46,033 shares for the year ended March 31, 2018, 2017 and 2016, respectively, because their effect will be anti-dilutive.

Related party

Related party	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Related party	25. Related party The following is a list of the Company’s subsidiaries as at March 31, 2018: Direct subsidiaries Step subsidiaries Place of incorporation WNS Global Services Netherlands Cooperatief U.A. The Netherlands WNS Global Services Philippines Inc. Philippines WNS Global Services (Romania) S.R.L. Romania WNS North America Inc. Delaware, USA WNS Business Consulting Services Private Limited India WNS Global Services Inc. Delaware, USA WNS BPO Services Costa Rica, S.R.L Costa Rica Denali Sourcing Services Inc. (1) Delaware, USA WNS Assistance Limited (previously WNS Workflow Technologies Limited) United Kingdom WNS Assistance (Legal) Limited (5) United Kingdom Accidents Happen Assistance Limited United Kingdom WNS Legal Assistance LLP (6) United Kingdom WNS (Mauritius) Limited Mauritius WNS Capital Investment Limited Mauritius - WNS Customer Solutions (Singapore) Private Limited Singapore -WNS Global Services (Australia) Pty Ltd Australia - WNS New Zealand Limited (7) New Zealand -Business Applications Associates Beijing Ltd China WNS Global Services Private Limited (8) India - WNS Global Services (UK) Limited (2) United Kingdom - WNS Global Services SA (Pty) Limited South Africa - WNS B-BBEE (3) South Africa - Ucademy (Pty) Limited (4) South Africa - MTS HealthHelp Inc. (9) Delaware, USA - HealthHelp Holdings LLC (9) Delaware, USA - HealthHelp LLC (9) Delaware, USA - Value Edge Inc. (10) Delaware, USA - Value Edge AG. (10) Switzerland - Value Edge GmbH (10) Germany WNS Global Services (Private) Limited Sri Lanka WNS Global Services (Dalian) Co. Ltd. China Notes: (1) On January 20, 2017, the Company acquired all outstanding equity shares of Denali Sourcing Services Inc. (2) WNS Global Services (UK) is jointly held by WNS Global Services Private Limited and WNS Holdings Limited. The percentage of holding of WNS Global Services Private Limited is 50.7% and of WNS Holdings Limited is 49.3%. (3) The WNS B-BBEE (4) Ucademy (Pty) Limited has been incorporated as a subsidiary of WNS Global Services SA (Pty) Limited with effect from June 20, 2016. (5) WNS Assistance (Legal) Limited, a wholly owned subsidiary of WNS Assistance Limited, was incorporated on April 20, 2016. (6) WNS Legal Assistance LLP is a limited liability partnership, organized under the laws of England and Wales in November 2014. WNS Legal Assistance LLP provides legal services in relation to personal injury claims within the Auto Claims BPM (as defined in Note 26) segment in the UK. During the year ended March 31, 2018, the Company acquired 20% of the equity capital of WNS Legal Assistance LLP from Prettys Solicitors (the non-controlling (7) WNS New Zealand Limited, a wholly owned subsidiary of WNS Global Services (Australia) Pty Ltd, was incorporated on June 13, 2017. (8) WNS Global Services Private Limited is held jointly by WNS (Mauritius) Limited and WNS Customer Solutions (Singapore) Private Limited. The percentage of holding of WNS (Mauritius) Limited is 80% and of WNS Customer Solutions (Singapore) Private Limited is 20%. (9) On March 15, 2017, the Company acquired all ownership interests of MTS HealthHelp Inc. and its subsidiaries, which existed on that date. HealthHelp Holdings LLC is 63.7% owned by MTS HealthHelp Inc. and 36.3% owned by WNS North America Inc. (10) On June 14, 2016, the Company acquired all outstanding equity shares of Value Edge Research Services Private Limited. As part of the acquisition, the Company also acquired the three subsidiaries of Value Edge Research Services Private Limited, which existed on that date. Value Edge Research Services Private Limited was merged with and into WNS Global Services Private Limited pursuant to a Scheme of Amalgamation approved by the National Company Law Tribunal on July 27, 2017. Name of the related party Relationship Acumentor Inc. (w.e.f. April 1, 2014) An entity of which a member of key management is the sole proprietor Razmatazz Events An entity which a close relative of the member of key management owns and controls Surface Architectural Supply Inc. (w.e.f. September 1, 2014) An entity in which a member of key management has a controlling stake J F Fitness of North America (w.e.f. September 1, 2014) An entity in which a member of key management has a controlling stake Sheron LLC (w.e.f. April 1, 2014) An entity which a member of key management and his close relative jointly own and control JF Manufacturing LLC ( w.e.f. May 22, 2017) An entity in which a member of key management has a controlling stake Haviland Digital Limited (w.e.f. July 1, 2017) An entity in which a member of key management has a sole controlling stake Mission Control Productions Limited (w.e.f. July 1, 2017) An entity in which a member of key management has a controlling stake Mirabilis Technology Services Limited (w.e.f. July 1, 2017) An entity in which a member of key management has a controlling stake Haviland Digital Co-Productions An entity in which a member of key management has a sole controlling stake 35 Yard Development (w.e.f July 1, 2017) An entity in which a member of key management has a joint controlling stake Vitality Risk LLC (w.e.f. October 27, 2017) An entity in which a member of key management has a sole controlling stake Key management personnel Adrian T. Dillon Chairman (Appointed as Chairman effective January 1, 2014, was Non-Executive Keshav R. Murugesh Director and Group Chief Executive Officer Jeremy Young (Ceased to be director from September 29, 2015) Director Renu S. Karnad Director Anthony A. Greener (Ceased to be director from September 27, 2016) Director Albert Aboody (Ceased to be director from September 27, 2017) Director Swaminathan Rajamani Chief People Officer Ronald Gillette Chief Operating Officer Sanjay Puria Group Chief Financial Officer Gareth Williams Director Michael Menezes Director John Freeland (Appointed on September 1, 2014) Director Francoise Gri (Appointed on May 6, 2015) Director Keith Haviland (Appointed on July 1, 2017) Director Mario Vitale (Appointed on October 27, 2017) Director Year ended March 31, Nature of transaction with related parties 2018 2017 2016 Key management personnel* Remuneration and short-term benefits 6,614 4,592 4,671 Defined contribution plan 94 89 84 Other benefits 17 15 14 Share-based compensation expense 17,677 13,347 8,674 * Defined benefit plan is not disclosed as these are determined for the Company as a whole.

Operating segments

Operating segments	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Operating segments	26. Operating segments The Company has several operating segments based on a mix of industry and the types of services. The composition and organization of these operating segments currently is designed in such a way that the back office shared processes, i.e. the horizontal structure, delivers service to industry specific back office and front office processes i.e. the vertical structure. These structures represent a matrix form of organization structure, accordingly operating segments have been determined based on the core principle of segment reporting in accordance with IFRS 8 “Operating segments” (“IFRS 8”). Segment managers are responsible for the performance of the operating segments on a combined vertical structure which includes travel, shipping and logistics services; utilities, retail and consumer products group; banking and financial, healthcare and insurance services including auto claims; and others. The segment managers’ performance is reviewed by the Group Chief Executive Officer, who has been identified as the Chief Operating Decision Maker (“CODM”). The CODM evaluates the Company’s performance and allocates resources based on revenue growth of combined vertical structure. The Company believes that the business process management services that it provides to customers in industries other than auto claims such as travel, shipping and logistics services; utilities, retail and consumer products group; banking and financial, healthcare and insurance; and others are similar in terms of services, service delivery methods, use of technology, and average long-term gross profit and hence meet the aggregation criteria in accordance with IFRS 8. WNS Assistance Limited and Accidents Happen Assistance Limited (which provide automobile repair through a network of third party repair centers), and WNS Assistance (Legal) Limited and WNS Legal Assistance LLP (which provides legal services in relation to personal injury claims), constitute WNS Auto Claims BPM, the performance of which is evaluated by the CODM separately. WNS Auto Claims BPM segment does not meet the aggregation criteria. Accordingly, the Company has determined that it has two reportable segments “WNS Global BPM” and “WNS Auto Claims BPM.” In order to provide accident management services, the Company arranges for the repair through a network of repair centers. Repair costs paid to automobile repair centers are invoiced to customers and recognized as revenue except in cases where the Company has concluded that it is not the principal in providing claims handling services and hence it would be appropriate to record revenue from repair services on a net basis i.e. net of repair cost. The Company uses revenue less repair payments (non-GAAP) non-GAAP “Non-fault “Non-fault” The segment results for the year ended March 31, 2018 are as follows: Year ended March 31, 2018 WNS Global BPM WNS Auto Claims BPM Inter segments* Total Revenue from external customers $ 722,542 $ 35,414 $ — $ 757,956 Segment revenue $ 722,600 $ 35,414 $ (58 ) $ 757,956 Payments to repair centers — 16,970 — 16,970 Revenue less repair payments (non-GAAP) 722,600 18,444 (58 ) 740,986 Depreciation 19,682 272 — 19,954 Other costs 561,870 18,249 (58 ) 580,061 Segment operating profit 141,048 (77 ) — 140,971 Other income, net (9,757 ) (1,473 ) — (11,230 ) Finance expense 4,065 199 — 4,264 Segment profit before income taxes 146,740 1,197 — 147,937 Provision for income taxes 15,319 112 — 15,431 Segment profit 131,421 1,085 — 132,506 Amortization of intangible assets 15,505 Share based compensation expense 30,565 Profit $ 86,436 Addition to non-current $ 32,337 $ 201 $ — $ 32,538 Total assets, net of elimination 633,186 126,377 — 759,563 Total liabilities, net of elimination $ 181,627 $ 82,980 $ — $ 264,607 * Transactions between inter segments represent invoices issued by WNS Global BPM to WNS Auto Claims BPM for business process management services rendered by the former to the latter. No client individually accounted for more than 10% of the total revenue during the year ended March 31, 2018. The segment results for the year ended March 31, 2017 are as follows: Year ended March 31, 2017 WNS Global BPM WNS Auto Claims BPM Inter segments* Total Revenue from external customers $ 557,904 $ 44,642 $ — $ 602,546 Segment revenue $ 557,983 $ 44,642 $ (79 ) $ 602,546 Payments to repair centers 24,102 — 24,102 Revenue less repair payments (non-GAAP) 557,983 20,540 (79 ) 578,444 Depreciation 16,598 305 — 16,903 Other costs 429,074 20,147 (79 ) 449,142 Impairment of goodwill (Refer note 9) — 21,673 — 21,673 Segment operating profit/(loss) 112,311 (21,585 ) — 90,726 Other income, net (7,785 ) (904 ) — (8,689 ) Finance expense 547 — — 547 Segment profit/(loss) before income taxes 119,549 (20,681 ) — 98,868 Provision for income taxes 17,441 89 — 17,530 Segment profit/(loss) 102,108 (20,770 ) — 81,338 Amortization of intangible assets 20,539 Share-based compensation expense 23,036 Profit/(loss) $ 37,763 Addition to non-current $ 111,280 $ 453 $ — $ 111,733 Total assets, net of elimination 590,974 113,149 — 704,123 Total liabilities, net of elimination $ 214,155 $ 74,902 $ — $ 289,057 * Transactions between inter segments represent invoices raised by WNS Global BPM on WNS Auto Claims BPM for business process outsourcing services rendered by the former to latter. One customer in the WNS Global BPM segment accounted for 9.0% of the Company’s total revenue for the year ended March 31, 2017. The receivables from this customer comprised 7.1% of the Company’s total trade receivables as at March 31, 2017. The segment results for the year ended March 31, 2016 are as follows: Year ended March 31, 2016 WNS Global BPM WNS Auto Claims BPM Inter segments* Total Revenue from external customers $ 508,864 $ 53,315 $ — $ 562,179 Segment revenue $ 509,268 $ 53,315 $ (404 ) $ 562,179 Payments to repair centers — 31,170 — 31,170 Revenue less repair payments (non-GAAP) 509,268 22,145 (404 ) 531,009 Depreciation 15,090 345 — 15,435 Other costs 377,051 22,966 (404 ) 399,613 Segment operating profit/(loss) 117,127 (1,166 ) — 115,961 Other income, net (7,461 ) (1,033 ) — (8,494 ) Finance expense 278 — — 278 Segment profit/(loss) before income taxes 124,310 (133 ) — 124,177 Provision for income taxes 20,905 275 — 21,180 Segment profit/(loss) 103,405 (408 ) — 102,997 Amortization of intangible assets 25,198 Share-based compensation expense 17,919 Profit/(loss) $ 59,880 Addition to non-current $ 30,757 $ 1,101 $ — $ 31,858 Total assets, net of elimination 373,195 152,256 — 525,451 Total liabilities, net of elimination $ 36,660 $ 80,602 $ — $ 117,262 * Transactions between inter segments represent invoices raised by WNS Global BPM on WNS Auto Claims BPM for business process outsourcing services rendered by the former to latter. One customer in the WNS Global BPM segment accounted for 10.9% of the Company’s total revenue for the year ended March 31, 2016. The receivables from this customer comprised 10.0% of the Company’s total trade receivables as at March 31, 2016. External Revenue Revenues from the geographic segments based on domicile of the customer. The Company’s external revenue by geographic area is as follows: Year ended March 31, 2018 2017 2016 Jersey, Channel Islands $ — $ — $ — US 308,436 196,193 155,345 UK 258,863 248,588 264,889 Australia 66,626 49,053 40,308 Europe (excluding UK) 47,169 37,494 34,732 South Africa 42,841 42,717 30,086 Rest of the world 34,021 28,501 36,819 Total $ 757,956 $ 602,546 $ 562,179 The Company’s non-current As at March 31, 2018 2017 Jersey, Channel Islands $ — $ — UK 756 1,228 North America 5,112 6,493 India 26,167 21,944 South Africa 10,529 11,449 Philippines 14,050 10,583 Rest of the world 3,992 3,099 Total $ 60,606 $ 54,796

Commitment and Contingencies

Commitment and Contingencies	12 Months Ended
	Mar. 31, 2018
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Commitment and Contingencies	27. Commitment and Contingencies Leases The Company has entered into various non-cancelable non-cancelable Operating lease Less than 1 year $ 27,572 1-3 47,115 3-5 29,783 More than 5 years 27,437 Total minimum lease payments $ 131,907 Rental expenses were $33,685, $27,712 and $24,313 for the years ended March 31, 2018, 2017, and 2016, respectively. Capital commitments As at March 31, 2018 and 2017, the Company had committed to spend approximately $5,762 and $6,257, respectively, under agreements to purchase property and equipment. These amounts are net of capital advances paid in respect of these purchases. Bank guarantees and others Certain subsidiaries of the Company hold bank guarantees aggregating $2,579 and $1,190 as at March 31, 2018 and 2017, respectively. These guarantees have a remaining expiry term ranging from one to five years. Restricted time deposits placed with bankers as security for guarantees given by them to regulatory authorities aggregating $575 and $355 as at March 31, 2018 and 2017, respectively, are included in other current assets. These deposits represent cash collateral against bank guarantees issued by the banks on behalf of the Company to third parties. Contingencies In the ordinary course of business, the Company is involved in lawsuits, claims and administrative proceedings. While uncertainties are inherent in the final outcome of these matters, the Company believes, after consultation with counsel, that the disposition of these proceedings will not have a material adverse effect on the Company’s financial position, results of operations or cash flows.

Additional capital disclosures

Additional capital disclosures	12 Months Ended
	Mar. 31, 2018
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Additional capital disclosures	28. Additional capital disclosures The key objective of the Company’s capital management is to ensure that it maintains a stable capital structure with the focus on total equity to uphold investor, creditor, and customer confidence and to ensure future development of its business. The Company focuses on keeping a strong total equity base to ensure independence, security, as well as a high financial flexibility for potential future borrowings, if required, without impacting the risk profile of the Company. The capital structure as at March 31, 2018 and 2017 was as follows: As at March 31, 2018 2017 % Change Total equity attributable to the equity shareholders of the Company $ 494,956 $ 415,066 19 % As percentage of total capital 85 % 78 % Long term debt(1) 89,900 118,000 (24 )% Total debt $ 89,900 $ 118,000 (24 )% As percentage of total capital 15 % 22 % Total capital (debt and equity) $ 584,856 $ 533,066 10 % Note: (1) Before netting off debt issuance cost of $769 and $1,257 as at March 31, 2018 and March 31, 2017, respectively. The Company is predominantly equity-financed. This is also evident from the fact that debt represents 15% and 22% of total capital as at March 31, 2018 and 2017, respectively.

Summary of significant accoun37

Summary of significant accounting policies (Policies)	12 Months Ended
	Mar. 31, 2018
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Basis of preparation	a. Basis of preparation These consolidated financial statements have been prepared in compliance with International Financial Reporting Standards (“IFRS”) as issued by the International Accounting Standard Board (“IASB”). These consolidated financial statements correspond to the classification provisions contained in IAS 1 (revised), “Presentation of Financial Statements.” Accounting policies have been applied consistently to all periods presented in these consolidated financial statements.
Basis of measurement	b. Basis of measurement These consolidated financial statements have been prepared on a historical cost convention and on an accrual basis, except for the following material items that have been measured at fair value as required by relevant IFRS:- a. Derivative financial instruments; b. Share-based payment transactions; c. Marketable securities and investments in mutual funds; d. Investments in fixed maturity plans (FMPs); and e. Contingent consideration.
Use of estimates and judgments	c. Use of estimates and judgments The preparation of financial statements in conformity with IFRS requires management to make judgments, estimates and assumptions that affect the application of accounting policies and the reported amount of assets, liabilities, income and expenses. Actual results may differ from those estimates. Estimates and underlying assumptions are reviewed on an ongoing basis. Revisions to accounting estimates are recognized in the period in which the estimates are revised and in any future period affected. In particular, information about significant areas of estimation, uncertainty and critical judgments in applying accounting policies that have the most significant effect on the amount recognized in the consolidated financial statements is included in the following notes: i. Revenue recognition The Company provides automobile claims handling services, wherein the Company enters into contracts with its clients to process all their claims over the contract period and the fees are determined either on a per claim basis or as a fixed payment for the contract period. Where the contracts are on a per claim basis, the Company invoices the client at the inception of the claim process. The Company estimates the processing period for the claims and recognizes revenue over the estimated processing period. This processing period generally ranges between one to two months. The processing time may be greater for new clients and the estimated service period is adjusted accordingly. The processing period is estimated based on historical experience and other relevant factors, if any. ii. Allowance for doubtful trade recevables The allowance for doubtful trade receivables is evaluated on a regular basis and adjusted based upon management’s best estimate of probable losses inherent in trade receivable. In estimating probable losses, the Company reviews accounts that are past due, non-performing iii. Current income taxes The major tax jurisdictions for the Company are India, South Africa, UK and US, though the Company also files tax returns in other foreign jurisdictions. Significant judgments are involved in determining the provision for income taxes including judgment on whether tax positions are probable of being sustained in tax assessments. A tax assessment can involve complex issues, which can only be resolved over extended time periods. The recognition of taxes that are subject to certain legal or economic limits or uncertainties is assessed individually by management based on the specific facts and circumstances. iv. Deferred income taxes The assessment of the probability of future taxable profit in which deferred tax assets can be utilized is based on the Company’s latest approved budget forecast, which is adjusted for significant non-taxable v. Impairment An impairment loss is recognized for the amount by which an asset’s or cash-generating unit’s carrying amount exceeds its recoverable amount. To determine the recoverable amount, management estimates expected future cash flows from each asset or cash-generating unit and determines a suitable interest rate in order to calculate the present value of those cash flows. In the process of measuring expected future cash flows management makes assumptions about future operating results. These assumptions relate to future events and circumstances. The actual results may vary, and may cause significant adjustments to the Company’s assets within the next financial year. The calculation of impairment loss involves significant estimates and assumptions which includes revenue and earnings multiples, growth rates and net margins used to calculate projected future cash flows, risk-adjusted discount rate, future economic and market conditions. In most cases, determining the applicable discount rate involves estimating the appropriate adjustment to market risk and the appropriate adjustment to asset-specific risk factors. vi. Valuation of derivative financial instruments Management uses valuation techniques in measuring the fair value of derivative financial instruments, where active market quotes are not available. In applying the valuation techniques, management makes maximum use of market inputs, and uses estimates and assumptions that are, as far as possible, consistent with observable data that market participants would use in pricing the instrument. Where applicable data is not observable, management uses its best estimate about the assumptions that market participants would make. These estimates may vary from the actual prices that would be achieved in an arm’s length transaction at the reporting date. vii. Accounting for defined benefit plans In accounting for pension and post-retirement benefits, several statistical and other factors that attempt to anticipate future events are used to calculate plan expenses and liabilities. These factors include expected return on plan assets, discount rate assumptions and rate of future compensation increases. To estimate these factors, actuarial consultants also use estimates such as withdrawal, turnover, and mortality rates which require significant judgment. The actuarial assumptions used by the Company may differ materially from actual results in future periods due to changing market and economic conditions, regulatory events, judicial rulings, higher or lower withdrawal rates, or longer or shorter participant life spans. viii. Share-based compensation expense The share-based compensation expense is determined based on the Company’s estimate of equity instruments that will eventually vest. ix. Business combinations Business combinations are accounted for using the acquisition method under the provisions of IFRS 3 (Revised) , “Business Combinations”. The cost of an acquisition is measured at the fair value of the assets transferred, equity instruments issued and liabilities incurred at the date of acquisition. The cost of the acquisition also includes the fair value of any contingent consideration. Identifiable tangible and intangible assets acquired and liabilities and contingent liabilities assumed in a business combination are measured initially at their fair value on the date of acquisition. Significant estimates are required to be made in determining the value of contingent consideration and intangible assets.
Basis of consolidation	d. Basis of consolidation The Company consolidates entities over which it has control. Control exists when the Company has existing rights that give the Company the current ability to direct the activities which affect the entity’s returns; the Company is exposed to or has rights to returns which may vary depending on the entity’s performance; and the Company has the ability to use its power to affect its own returns from its involvement with the entity. Subsidiaries are consolidated from the date control commences until the date control ceases. i. Business combinations Business combinations are accounted for using the acquisition method under the provisions of IFRS 3 (Revised) , “Business Combinations”. The cost of an acquisition is measured at the fair value of the assets transferred, equity instruments issued and liabilities incurred at the date of acquisition. The consideration of the acquisition also includes the fair value of any contingent consideration. Identifiable tangible and intangible assets acquired and liabilities and contingent liabilities assumed in a business combination are measured initially at their fair value on the date of acquisition. Significant estimates are required to be made in determining the value of contingent consideration and intangible assets. Transaction costs that the Company incurs in connection with a business combination such as finders’ fees, legal fees, due diligence fees, and other professional and consulting fees are expensed as incurred. ii. Transactions eliminated on consolidation All significant inter-company and intra-company balances, transactions, income and expenses including unrealized income or expenses are eliminated on consolidation.
Functional and presentation currency	e. Functional and presentation currency The financial statements of each of the Company’s subsidiaries are presented using the currency of the primary economic environment in which these entities operate (i.e. the functional currency). The consolidated financial statements are presented in US dollars (USD) which is the presentation currency of the Company and has been rounded off to the nearest thousands.
Foreign currency transactions and translation	f. Foreign currency transactions and translation i. Transactions in foreign currency Transactions in foreign currency are translated into the functional currency using the exchange rates prevailing at the dates of the transactions. Foreign exchange gains and losses resulting from the settlement of such transactions and from the translation at the exchange rates prevailing at the reporting date of monetary assets and liabilities denominated in foreign currencies are recognized in the consolidated statement of income. Gains/losses relating to translation or settlement of trading activities are disclosed under foreign exchange gains/losses and translation or settlements of financing activities are disclosed under finance expenses. In the case of foreign exchange gains/losses on borrowings that are considered as a natural economic hedge for the foreign currency monetary assets, such foreign exchange gains/losses, net are presented within results from operating activities. ii. Foreign operations For the purpose of presenting consolidated financial statements, the assets and liabilities of the Company’s foreign operations that have local functional currency are translated into US dollars using exchange rates prevailing at the reporting date. Income and expense are translated at the monthly average exchange rate for the respective period. Exchange differences arising, if any, are recorded in equity as part of the Company’s other comprehensive income. Such exchange differences are recognized in the consolidated statement of income in the period in which such foreign operations are disposed. Goodwill and fair value adjustments arising on the acquisition of foreign operation are treated as assets and liabilities of the foreign operation and translated at the exchange rate prevailing at the reporting date. Foreign currency exchange differences arising from intercompany receivables or payables relating to foreign operations, the settlement of which is neither planned nor likely to occur in the foreseeable future, are considered to form part of net investment in foreign operation and are recognized in foreign currency translation reserve.
Financial instruments - initial recognition and subsequent measurement	g. Financial instruments — initial recognition and subsequent measurement Financial instruments are classified in the following categories: • Non-derivative available-for-sale. • Non-derivative • Derivative financial instruments under the category of financial assets or financial liabilities at FVTPL. The classification of financial instruments depends on the purpose for which those were acquired. Management determines the classification of the Company’s financial instruments at initial recognition. i. Non-derivative a) Loans and receivables Loans and receivables are non-derivative non-current b) Financial assets designated as FVTPL Financial assets at FVTPL include financial assets that are either classified as held for trading if acquired principally for the purpose of selling in the short term or that meet certain conditions and are designated at FVTPL upon initial recognition. Financial assets are initially measured at fair value. Transaction costs directly attributable to the acquisition of financial assets at fair value through profit or loss are recognized immediately in profit or loss. Assets in this category are measured at fair value with changes therein recognized in profit or loss. The fair values of financial assets in this category are determined by reference to active market transactions or using a valuation technique where no active market exists. Assets in this category are classified as current assets if expected to be settled within 12 months, otherwise they are classified as non-current. c) Available-for-sale Available-for-sale non-derivative Available-for-sale ii. Non-derivative All financial liabilities are recognized initially at fair value, except in the case of loans and borrowings which are recognized at fair value net of directly attributable transaction costs. The Company’s financial liabilities include trade and other payables, bank overdrafts, contingent consideration and loans and borrowings. Trade and other payables maturing later than 12 months after the reporting date are presented as non-current After initial recognition, interest bearing loans and borrowings are subsequently measured at amortized cost using the effective interest rate method. Gains and losses are recognized in the consolidated statement of income when the liabilities are derecognized as well as through the effective interest rate method amortization process. After initial recognition, contingent consideration are subsequently measured at fair value and the changes to the fair value are recognized in the consolidated statement of income. iii. Derivative financial instruments and hedge accounting The Company is exposed to foreign currency fluctuations on foreign currency assets, liabilities, net investment in foreign operations and forecasted cash flows denominated in foreign currency. The Company limits the effect of foreign exchange rate fluctuation by following established risk management policies including the use of derivatives. The Company enters into derivative financial instruments where the counter party is a bank. The Company holds derivative financial instruments such as foreign exchange forward, option contracts and interest rate swaps to hedge certain foreign currency and interest rate exposures. Cash flow hedges The Company recognizes derivative instruments as either assets or liabilities in the statement of financial position at fair value. Derivative instruments qualify for hedge accounting when the instrument is designated as a hedge; the hedged item is specifically identifiable and exposes the Company to risk; and it is expected that a change in fair value of the derivative instrument and an opposite change in the fair value of the hedged item will have a high degree of correlation. For derivative instruments where hedge accounting is applied, the Company records the effective portion of derivative instruments that are designated as cash flow hedges in other comprehensive income (loss) in the statement of comprehensive income, which is reclassified into earnings in the same period during which the hedged item affects earnings. The remaining gain or loss on the derivative instrument in excess of the cumulative change in the present value of future cash flows of the hedged item, if any (i.e., the ineffective portion) or hedge components excluded from the assessment of effectiveness, and changes in fair value of other derivative instruments not designated as qualifying hedges is recorded as gains/losses, net in the consolidated statement of income. Gains/losses on cash flow hedges on intercompany forecasted revenue transactions are recorded in foreign exchange gains/losses and cash flow hedge on interest rate swaps are recorded in finance expense. Cash flows from the derivative instruments are classified within cash flows from operating activities in the statement of cash flows. iv. Offsetting of financial instruments Financial assets and financial liabilities are offset against each other and the net amount reported in the consolidated statement of financial position if, and only if, there is a currently enforceable legal right to offset the recognized amounts and there is an intention to settle on a net basis, or to realize the assets and settle the liabilities simultaneously. v. Fair value of financial instruments The fair value of financial instruments that are traded in active markets at each reporting date is determined by reference to quoted market prices or dealer price quotations, without any deduction for transaction costs. For financial instruments not traded in an active market, the fair value is determined using appropriate valuation models. Where applicable, these models project future cash flows and discount the future amounts to a present value using market-based observable inputs including interest rate curves, credit risk, foreign exchange rates, and forward and spot prices for currencies. vi. Impairment of financial assets The Company assesses at each reporting date whether there is objective evidence that a financial asset or a group of financial assets is impaired. A financial asset is considered impaired if objective evidence indicates that one or more events have had a negative effect on the estimated future cash flows of that asset. Individually significant financial assets are tested for impairment on an individual basis. The remaining financial assets are assessed collectively in groups that share similar credit risk characteristics. a) Loans and receivables Impairment loss in respect of loans and receivables measured at amortized cost are calculated as the difference between their carrying amount, and the present value of the estimated future cash flows discounted at the original effective interest rate. Such impairment loss is recognized in the consolidated statement of income. b) Available-for-sale Significant or prolonged decline in the fair value of the security below its cost and the disappearance of an active trading market for the security are objective evidence that the security is impaired. An impairment loss in respect of an available-for-sale
Equity and share capital	h. Equity and share capital i. Share capital and share premium The Company has only one class of equity shares. Par value of the equity share is recorded as the share capital and the amount received in excess of par value is classified as share premium. The credit corresponding to the share-based compensation expense and excess tax benefit related to the exercise of share options and restricted share units is recorded in share premium. ii. Retained earnings Retained earnings comprise the Company’s undistributed earnings after taxes. iii. Other components of equity Other components of equity consist of the following: Cash flow hedging reserve Changes in fair value of derivative hedging instruments designated and effective as a cash flow hedge are recognized net of taxes. Foreign currency translation reserve Foreign currency translation reserve consists of (i) the exchange difference arising from the translation of the financial statements of foreign subsidiaries and (ii) foreign currency differences arising from intercompany receivables or payables relating to foreign operations, the settlement of which is neither planned nor likely to occur in the foreseeable future, which are considered to form part of net investment in foreign operation Pension adjustments This reserve represents cumulative actuarial gain and losses recognized, net of taxes on defined benefits plans.
Cash and cash equivalents	i. Cash and cash equivalents The Company considers all highly liquid investments with an initial maturity of up to three months to be cash equivalents. Cash equivalents are readily convertible into known amounts of cash and subject to an insignificant risk of changes in value.
Investments	j. Investments i. Marketable securities and mutual funds The Company’s marketable securities represent liquid investments and are acquired principally for the purpose of earning daily dividend income. All additions and redemptions of such investments are recognized on the trade date. Investments are initially measured at cost, which is the fair value of the consideration paid, including transaction costs. Marketable securities classified under the Available-for-sale Investments in mutual funds represent investments in mutual fund schemes wherein the mutual fund issuer has invested these funds in enterprise development funds. These investments are carried at fair value, with changes in fair value recognized in other comprehensive income. The fair value represents the original cost of the investment and the investment’s fair value at each reporting period. Investments in mutual funds have been designated as available for sale. ii. Investments in fixed maturity plans The Company’s investments in fixed maturity plans (“FMPs”) represent investments in mutual fund schemes wherein the mutual fund issuer has invested these funds in certificate of deposits with banks in India. The investments in FMPs are designated as fair value through profit or loss and change in fair value is recognized in the consolidated statement of income. The fair value represents original cost of an investment and the investment’s fair value at each reporting period or net asset value (“NAV”) as quoted. The Company manages FMPs on a fair value basis in accordance with the entity’s documented risk management, investment strategy and information provided to the key managerial personnel. The returns on the investment are measured based on the fair value movement rather than looking at the overall returns on the maturity. The Company’s investment purchase and sale decisions are also based on the fair value fluctuations rather than a predetermined policy to hold the investment until maturity. Key management personnel believe that recording these investments through the consolidated statement of income would provide more relevant information to measure the performance of the investment. iii. Investments in fixed deposits Investments in fixed deposits consist of term deposits with original maturities of more than three months with banks. These are designated as Loans and Receivables.
Funds held for clients	k. Funds held for clients Some of the Company’s agreements in the auto claims handling services allow the Company to temporarily hold funds on behalf of the client. The funds are segregated from the Company’s funds and there is usually a short period of time between when the Company receives these funds from the client and when the payments are made on their behalf.
Property and equipment	l. Property and equipment Property and equipment are stated at historical cost. Cost includes expenditures directly attributable to the acquisition of the asset. Depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets, which are as follows: Asset description Asset life (in years) Buildings 20 Computers and software 3-4 Furniture, fixtures and office equipment 2-5 Vehicles 3 Leasehold improvements Lesser of estimated useful life or lease term Assets acquired under finance leases are capitalized as assets by the Company at an amount equal to the fair value of the leased asset or, if lower, the present value of the minimum lease payments, each determined at the inception of the lease. Assets under finance leases and leasehold improvements are depreciated over the shorter of the lease term or the estimated useful life of the assets. Advances paid towards the acquisition of property and equipment and the cost of property and equipment not ready for use before the reporting date are disclosed as capital work-in-progress The Company assesses property and equipment for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or group of assets may not be recoverable. If any such indication exists, the Company estimates the recoverable amount of the asset. The recoverable amount of an asset or cash generating unit is the higher of its fair value less cost of disposal (“FVLCOD”) and its value-in-use
Goodwill	m. Goodwill Goodwill represents the excess of the cost of an acquisition over the fair value of the Company’s share of the net identifiable assets of the acquired subsidiary at the date of acquisition. Goodwill is allocated to the cash-generating units expected to benefit from the synergies of the combination for the purpose of impairment testing. Goodwill is tested, at the cash-generating unit (or group of cash generating units) level, for impairment annually or if events or changes in circumstances indicate that the carrying amount may not be recoverable. Goodwill is carried at cost less accumulated impairment losses. Impairment loss on goodwill is not reversed. See further discussion on impairment testing under “Impairment of intangible assets and goodwill” below.
Intangible assets	n. Intangible assets Intangible assets are recognized only when it is probable that the expected future economic benefits attributable to the assets will accrue to the Company and the cost can be reliably measured. Intangible assets acquired in a business combination are recorded at fair value using generally accepted valuation methods appropriate for the type of intangible asset. Intangible assets with definite lives are amortized over the estimated useful lives and are reviewed for impairment, if indicators of impairment arise. Intangible assets with indefinite lives are not amortized but instead are tested for impairment at least annually and written down to the fair value. See further discussion on impairment testing under “Impairment of intangible assets and goodwill” below. Software Development Costs Costs incurred for developing software or enhancements to the existing software products to be sold and/or used for internal use are capitalized once the research phase is complete, technological feasibility and commercial feasibility has been established, future economic benefits are probable, the Company has an intention and ability to complete and use or sell the software and the costs can be measured reliably. Technological feasibility is established upon completion of a detailed design program or, in its absence, completion of a working model. Significant management judgments and estimates are utilized in the assessment of when technological feasibility is established, as well as in the ongoing assessment of the recoverability of capitalized costs. Costs that qualify as software development costs include external direct costs of materials and services utilized in developing or obtaining software and compensation and related benefits for employees who are directly associated with the software project. The capitalized costs are amortized on a straight-line basis over the estimated useful life. Costs associated with research phase activities, training, maintenance and all post-implementation stage activities are expensed as incurred. The Company’s definite lived intangible assets are amortized over the estimated useful life of the assets on a straight-line basis, as given below. Asset description Weighted average amortization period (in months) Customer contracts 48 Customer relationships 217 Covenant not-to-compete 48 Trade names 34 Technology 94 Intellectual Property and other rights 24 Software 55 Service mark Indefinite useful
Impairment of intangible assets and goodwill	o. Impairment of intangible assets and goodwill Goodwill is not subject to amortization and tested at least annually for impairment or whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. Intangible assets that are subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. An impairment loss is recognized for the amount by which the asset’s carrying amount exceeds its recoverable amount. The recoverable amount is the higher of an asset’s FVLCOD and VIU. For the purposes of assessing impairment, assets are grouped at the cash generating unit level which is the lowest level for which there are separately identifiable cash flows. Impairment losses recognized in respect of cash generating units are allocated first to reduce the carrying amount of any goodwill allocated to the cash generating units (or group of cash generating units) and then, to reduce the carrying amount of the other assets in the cash generating unit (or group of cash generating units) on a pro rata basis based on the carrying amount of each asset in the cash generating unit. Intangible assets except goodwill that suffered impairment are reviewed for possible reversal of the impairment at each reporting date.
Employee benefits	p. Employee benefits i. Defined contribution plans US Savings Plan Eligible employees of the Company in the US participate in a savings plan (“the Plan”) under Section 401(k) of the United States Internal Revenue Code (“the Code”). The Plan allows for employees to defer a portion of their annual earnings on a pre-tax UK Pension Scheme Eligible employees in the UK contribute to a defined contribution pension scheme operated in the UK. The assets of the scheme are held separately in an independently administered fund. The pension expense represents contributions payable to the fund maintained by the Company. Provident Fund Eligible employees of the Company in India, the Philippines, South Africa, Sri Lanka and the UK participate in a defined contribution fund in accordance with the regulatory requirements in the respective jurisdictions. Both the employee and the Company contribute an equal amount to the fund which is equal to a specified percentage of the employee’s salary. The Company has no further obligation under defined contribution plans beyond the contributions made under these plans. Contributions are charged to profit or loss and are included in the consolidated statement of income in the year in which they accrue. ii. Defined benefit plan Employees in India, the Philippines and Sri Lanka are entitled to a defined benefit retirement plan covering eligible employees of the Company. The plan provides for a lump-sum Gratuity liabilities are determined by actuarial valuation, performed by an independent actuary, at each reporting date using the projected unit credit method. The Company recognizes the net obligation of a defined benefit plan in its balance sheet as an asset or liability, as the case may be, in accordance with IAS 19, “Employee Benefits.” iii. Compensated absences The Company’s liability for compensated absences, which are expected to be utilized or settled within one year, is determined on an accrual basis for the carried forward unused vacation balances standing to the credit of each employee as at year-end The Company’s liability for compensated absences, which are expected to be utilized after one year is determined on the basis of an actuarial valuation using the projected unit credit method and is charged to consolidated statement of income in the year in which they accrue.
Share-based payments	q. Share-based payments The Company accounts for share-based compensation expense relating to share-based payments using a fair value method in accordance with IFRS 2 “Share-based Payments.”
Provisions and accrued expenses	r. Provisions and accrued expenses A provision is recognized in the statement of financial position when the Company has a present legal or constructive obligation as a result of a past event, and it is probable that an outflow of economic benefits will be required to settle the obligation. If the effect is material, provisions are recognized at present value by discounting the expected future cash flows at a pre-tax Provisions for onerous contracts are recognized when the expected benefits to be derived by the Company from a contract are lower than the unavoidable costs of meeting the future obligations under the contract. The provision is measured at the present value of the lower of the expected cost of terminating the contract and the expected net cost of continuing with the contract. Before a provision is established, the Company recognizes any impairment loss on the assets associated with that contract.
Revenue recognition	s. Revenue recognition The Company derives revenue from BPM services comprising of back office administration, data management, customer interaction services management and auto claims handling services. Revenue is recognized to the extent it is probable that the economic benefit will flow to the Company, the amount of revenue can be measured reliably, collection is probable, and the cost incurred or to be incurred can be measured reliably. Revenue from rendering services is recognized on an accrual basis when services are performed and revenue from the end of last billing to the reporting date is recognized as unbilled revenue. Revenue is net of value-added taxes and includes reimbursements of out-of-pocket Revenue earned by back office administration, data management and customer interaction services management services Back office administration, data management and customer interaction services contracts are based on the following pricing models: a) per full-time-equivalent arrangements, which typically involve billings based on the number of full-time employees (or equivalent) deployed on the execution of the business process outsourced; b) per transaction arrangements, which typically involve billings based on the number of transactions processed (such as the number of e-mail c) subscription arrangements, which typically involve billings based on per member per month, based on contractually agreed rates; d) fixed-price arrangements, which typically involve billings based on achievements of pre-defined e) outcome-based arrangements, which typically involve billings based on the business result achieved by our clients through our service efforts (such as measured based on a reduction in days sales outstanding, improvement in working capital, increase in collections or a reduction in operating expenses); or f) other pricing arrangements, including cost-plus arrangements, which typically involve billing the contractually agreed direct and indirect costs and a fee based on the number of employees deployed under the arrangement. Revenues from the Company’s services are recognized primarily on a time-and-material, time-and-material mark-up. Amounts billed or payments received, where revenue recognition criteria have not been met, are recorded as deferred revenue and are recognized as revenue when all the recognition criteria have been met. However, the costs related to the performance of BPM services unrelated to transition services (see discussion below) are recognized in the period in which the services are rendered. An upfront payment received towards future services is recognized ratably over the period when such services are provided. The Company has certain minimum commitment arrangements that provide for a minimum revenue commitment on an annual basis. Any revenue shortfall as compared to minimum commitment is invoiced and recognized at the reporting period end. For certain BPM customers, the Company performs transition activities at the outset of entering into a new contract. The Company has determined these transition activities do not meet the criteria using the guidance in IAS 18 “Revenue” Revenue earned by auto claims handling services Auto claims handling services include claims handling and administration (“Claims Handling”), car hire and arranging for repairs with repair centers across the UK and the related payment processing for such repairs (“Accident Management”).With respect to Claims Handling, the Company receives either a per-claim In order to provide Accident Management services, the Company arranges for the repair through a network of repair centers. The repair costs are invoiced to customers. In determining whether the receipt from the customers related to payments to repair centers should be recognized as revenue, the Company considers the criteria established by IAS 18, Illustrative example (“IE”) 21 — “Determining whether an entity is acting as a principal or as an agent.” a) the Company has the primary responsibility for providing the services, b) the Company negotiates labor rates with repair centers, c) the Company is responsible for timely and satisfactory completion of repairs, and d) the Company bears the risk that the customer may not pay for the services provided (credit risk). If there are circumstances where the above criteria are not met and therefore the Company is not the principal in providing Accident Management services, amounts received from customers are recognized and presented net of payments to repair centers in the consolidated statement of income. Revenue from Accident Management services is recorded net of the repairer referral fees passed on to customers. Revenue from legal services in the Auto claims BPM segment is recognized on the admission of liability by the third party to the extent of fixed fees earned at each stage and any further income on the successful settlement of the claim. Incremental and direct costs incurred to contract with a claimant are amortized over the estimated period of provision of services, not exceeding 15 months. All other costs to the Company are expensed as incurred.
Leases	t. Leases The Company leases most of its delivery centers and office facilities under operating lease agreements that are renewable on a periodic basis at the option of the lessor and the lessee. The lease agreements contain rent free periods and rent escalation clauses. Rental expenses for operating leases with step rents are recognized on a straight-line basis over the lease term. When a lease agreement undergoes a substantial modification of the existing terms, it would be accounted as a new lease agreement with the resultant deferred rent liability credited to the consolidated statement of income. Leases under which the Company assumes substantially all the risks and rewards of ownership are classified as finance leases. When acquired, such assets are capitalized at fair value or present value of the minimum lease payments at the inception of the lease, whichever is lower.
Income taxes	u. Income taxes Income tax comprises current and deferred tax. Income tax expense is recognized in consolidated statement of income except to the extent it relates to items directly recognized in equity, in which case it is recognized in equity. i. Current income tax Current income tax for the current and prior periods are measured at the amount expected to be recovered from or paid to the taxation authorities based on the taxable profit for the period. The tax rates and tax laws used to compute the amount are those that are enacted by the reporting date and applicable for the period. The Company offsets current tax assets and current tax liabilities, where it has a legally enforceable right to set off the recognized amounts and where it intends either to settle on a net basis, or to realize the asset and liability simultaneously. Significant judgments are involved in determining the provision for income taxes including judgment on whether tax positions are probable of being sustained in tax assessments. A tax assessment can involve complex issues, which can only be resolved over extended time periods. The recognition of taxes that are subject to certain legal or economic limits or uncertainties is assessed individually by management based on the specific facts and circumstances. Though the Company has considered all these issues in estimating its income taxes, there could be an unfavorable resolution of such issues that may affect results of the Company’s operations. ii. Deferred income tax Deferred income tax is recognized using the balance sheet approach. Deferred income tax assets and liabilities are recognized for all deductible and taxable temporary differences arising between the tax bases of assets and liabilities and their carrying amount in financial statements, except when the deferred income tax arises from the initial recognition of goodwill or an asset or liability in a transaction that is not a business combination and affects neither accounting nor taxable profits or loss at the time of transaction. Deferred income tax assets and liabilities are measured at the tax rates that are expected to apply in the period when the asset is realized or the liability is settled, based on tax rates (and tax laws) that have been enacted or substantively enacted at the reporting date. Deferred income tax asset in respect of carry forward of unused tax credits and unused tax losses are recognized to the extent that it is probable that taxable profit will be available against which the deductible temporary differences, and the carry forward of unused tax credits and unused tax losses can be utilized. The carrying amount of deferred income tax assets is reviewed at each reporting date and reduced to the extent that it is no longer probable that sufficient taxable profit will be available to allow all or part of the deferred income tax asset to be utilized. The Company recognizes deferred tax liabilities for all taxable temporary differences except those associated with the investments in subsidiaries where the timing of the reversal of the temporary difference can be controlled and it is probable that the temporary difference will not reverse in the foreseeable future.
Finance expense	v. Finance expense Finance expense comprises interest cost on borrowings, transaction costs and the gains/losses on settlement of related derivative instruments. The foreign exchange gains/losses on borrowings are considered as a natural economic hedge for the foreign currency monetary assets which are classified as foreign exchange gains/losses, net within results from operating activities. Borrowing costs are recognized in the consolidated statement of income using the effective interest method.
Earnings per share	w. Earnings per share Basic earnings per share are computed using the weighted-average number of ordinary shares outstanding during the period. Diluted earnings per share is computed by considering the impact of the potential issuance of ordinary shares, using the treasury stock method, on the weighted average number of shares outstanding during the period, except where the results would be anti-dilutive.
Government grants	x. Government grants The Company recognizes government grants only when there is reasonable assurance that the conditions attached to them shall be complied with, and the grants will be received. Government grants related to depreciable assets are treated as deferred income and are recognized in the consolidated statement of income on a systematic and rational basis over the useful life of the asset. Government grants related to revenue are recognized on a systematic basis in the consolidated statement of income, generally over the periods necessary to match them with the related costs that they are intended to compensate.

Summary of significant accoun38

Summary of significant accounting policies (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Estimated Useful Lives of Property and Equipment	Depreciation and amortization is computed using the straight-line method over the estimated useful lives of the assets, which are as follows: Asset description Asset life (in years) Buildings 20 Computers and software 3-4 Furniture, fixtures and office equipment 2-5 Vehicles 3 Leasehold improvements Lesser of estimated useful life or lease term
Estimated Useful Life of Intangible Assets	The Company’s definite lived intangible assets are amortized over the estimated useful life of the assets on a straight-line basis, as given below. Asset description Weighted average amortization period (in months) Customer contracts 48 Customer relationships 217 Covenant not-to-compete 48 Trade names 34 Technology 94 Intellectual Property and other rights 24 Software 55 Service mark Indefinite useful

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Mar. 31, 2018
MTS HealthHelp Inc. [member]
Purchase Price Allocation to Assets Acquired and Liabilities Assumed	The purchase price has been allocated, as set out below, to the assets acquired and liabilities assumed in the business combination. Amount Cash $ 3,119 Trade receivables 4,910 Unbilled revenue 2,016 Prepayments and other current assets 1,060 Property and equipment 4,612 Intangible assets - Software 1,274 - Customer contracts 4,537 - Customer relationships 49,584 - Service mark 400 - Covenant not-to-compete 4,693 - Technology 4,852 Non-current 161 Term loan (29,249 ) Current liabilities (2,555 ) Non-current (1,423 ) Deferred tax liability (18,163 ) Net assets acquired $ 29,828 Less: Purchase consideration 68,910 Goodwill on acquisition $ 39,082
Denali Sourcing Services Inc. [member]
Purchase Price Allocation to Assets Acquired and Liabilities Assumed	The purchase price has been allocated, as set out below, to the assets acquired and liabilities assumed in the business combination. Amount Cash $ 1,204 Trade receivables 2,799 Unbilled revenue 1,258 Prepayments and other current assets 95 Property and equipment 53 Deferred tax asset 18 Intangible assets - Software 3 - Customer contracts 3,025 - Customer relationships 8,000 - Trade name 545 - Covenant not-to-compete 1,718 Non-current 27 Current liabilities (3,781 ) Short-term line of credit (475 ) Non-current (343 ) Deferred tax liability (5,020 ) Net assets acquired $ 9,126 Less: Purchase consideration 38,668 Goodwill on acquisition $ 29,542
Value Edge Research Services Private Limited [member]
Purchase Price Allocation to Assets Acquired and Liabilities Assumed	The purchase price has been allocated, as set out below, to the assets acquired and liabilities assumed in the business combination. Amount Cash $ 432 Trade receivables 370 Unbilled revenue 706 Investments 87 Prepayments and other current assets 99 Property and equipment 78 Deferred tax asset 49 Intangible assets - Software 10 - Customer contracts 701 - Customer relationships 1,894 - Trade name 104 - Covenant not-to-compete 2,655 - Technology 1,238 Non-current 74 Current liabilities (1,236 ) Non-current (126 ) Deferred tax liability (2,281 ) Net assets acquired $ 4,854 Less: Purchase consideration 18,265 Goodwill on acquisition $ 13,411
Telkom SA SOC Limited [member]
Purchase Price Allocation to Assets Acquired and Liabilities Assumed	The purchase price has been allocated as follows: Amount Customer contract- intangible assets $ 2,990 Cash 411 Accrued leave liability (411 ) Deferred tax liabilities (837 ) Net assets acquired $ 2,153 Less: Purchase consideration 3,331 Goodwill on acquisition $ 1,178

Cash and cash equivalents (Tabl

Cash and cash equivalents (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Cash and Cash Equivalents	The Company considers all highly liquid investments with an initial maturity of up to three months to be cash equivalents. Cash and cash equivalents consist of the following: As at March 31, March 31, 2018 2017 Cash and bank balances $ 47,738 $ 46,110 Short term deposits with banks 52,091 23,693 Total $ 99,829 $ 69,803

Investments (Tables)

Investments (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Investments	Investments consist of the following: As at March 31, March 31, 2018 2017 Investments in marketable securities and mutual funds (1) $ 99,954 $ 87,652 Investments in FMPs — 96 Investment in fixed deposits 21,548 24,673 Total $ 121,502 $ 112,421 Note: (1) Marketable securities represent short term investments made principally for the purpose of earning dividend income. As at March 31, 2018 March 31, 2017 Current investments $ 120,960 $ 111,992 Non-current 542 429 Total $ 121,502 $ 112,421

Trade receivables, net (Tables)

Trade receivables, net (Tables) - Trade receivables [member]	12 Months Ended
	Mar. 31, 2018
Summary of Trade Receivables	Trade receivables consist of the following: As at March 31, March 31, 2018 2017 Trade receivables $ 71,952 $ 62,136 Less: Allowances for doubtful trade receivable (564 ) (1,713 ) Total $ 71,388 $ 60,423
Movement in Allowances for Doubtful Trade Receivable	The movement in the allowances for doubtful trade receivable is as follows: Year ended March 31, 2018 2017 2016 Balance at the beginning of the year $ 1,713 $ 4,446 $ 5,336 Charged to operations 2,115 777 1,010 Write-offs, net of collections (1,136 ) (2,571 ) (936 ) Reversals (2,321 ) (664 ) (904 ) Translation adjustment 193 (275 ) (60 ) Balance at the end of the year $ 564 $ 1,713 $ 4,446

Prepayments and other assets (T

Prepayments and other assets (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Prepayment and Other Assets	Prepayment and other assets consist of the following: As at March 31, 2018 March 31, 2017 Current: Service tax and other tax receivables $ 6,569 $ 8,029 Deferred transition cost 571 423 Employee receivables 1,099 1,215 Advances to suppliers 2,877 2,087 Prepaid expenses 7,994 8,819 Restricted cash, held in escrow (Refer Note 4(c)) 1,535 1,611 Other assets 4,202 5,201 Total $ 24,847 $ 27,385 Non-current: Deposits $ 8,708 $ 7,569 Income tax assets 12,595 10,202 Service tax and other tax receivables 11,410 6,236 Deferred transition cost 2,467 365 Restricted cash, held in escrow (Refer Note 4(c)) 1,535 3,222 Others assets 5,673 4,350 Total $ 42,388 $ 31,944

Goodwill (Tables)

Goodwill (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of the Carrying Value of Goodwill	A suumary of the carrying value of goodwill is as follows: As at March 31, March 31, 2018 2017 Gross carrying amount $ 159,500 $ 155,681 Accumulated impairment of goodwill (24,314 ) (21,673 ) Total $ 135,186 $ 134,008
Summary of Movement in Goodwill by Reportable Segment	The movement in goodwill balance by reportable segment as at March 31, 2018 and 2017 is as follows: Gross carrying amount WNS WNS Auto Global BPM Claims BPM Total Balance as at April 1, 2016 $ 46,503 $ 29,739 $ 76,242 Goodwill initially arising on acquisitions 82,127 — 82,127 Foreign currency translation 1,248 (3,936 ) (2,688 ) Balance as at March 31, 2017 $ 129,878 $ 25,803 $ 155,681 Goodwill arising on acquisitions (92 ) — (92 ) Foreign currency translation 767 3,144 3,911 Balance as at March 31, 2018 $ 130,553 $ 28,947 $ 159,500 Accumulated impairment losses WNS WNS Auto Global BPM Claims BPM Total Balance as at April 1, 2016 $ — $ — $ — Impairment of goodwill recognized during the year — 21,673 21,673 Balance as at March 31, 2017 $ — $ 21,673 $ 21,673 Impairment of goodwill recognized during the year — — — Foreign currency translation adjustment — 2,641 2,641 Balance as at March 31, 2018 — 24,314 24,314
Carrying Value of Goodwill Allocated to Cash Generating Units	The carrying value of goodwill allocated to the cash generating units (“CGU”) is as follows: As at March 31, March 31, 2018 2017 WNS Global BPM* $ 3,815 $ 3,815 South Africa 5,581 4,963 Research & Analytics 48,901 49,146 Technology services 3,632 3,238 WNS Auto Claims BPM 4,633 4,130 Finance and accounting 29,542 29,874 Healthcare 39,082 38,842 $ 135,186 $ 134,008 * Excluding South Africa, Research & analytics, Technology services, Finance and accounting and Healthcare goodwill.
Key Assumptions Used in Performing Impairment Test, by each CGU	The key assumptions used in performing the impairment test, by each CGU, were as follows: CGU’s WNS Global BPM* South Africa Finance & accounting Research & analytics Healthcare Technology services WNS Auto Claims BPM Discount rate 16.0 % 17.1 % 15.1 % 16.0 % 13.0 % 14.0 % 14.0 % Perpetual growth rate 3.0 % 3.0 % 2.0 % 3.0 % 2.5 % 3.0 % 2.0 % * Excluding South Africa, Research & analytics, Technology services, Healthcare and Finance & Accounting.

Intangible assets (Tables)

Intangible assets (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Change in Carrying Value of Intangible Assets	The changes in the carrying value of intangible assets for the year ended March 31, 2017 are as follows: Gross carrying value Customer contracts Customer relationships Intellectual property rights Trade names Technology Leasehold benefits Covenant not-to- compete Service mark Software Total Balance as at April 1, 2016 $ 156,786 $ 63,147 $ 4,450 $ — $ — $ 1,835 $ 326 — $ 19,760 $ 246,304 Additions — — — — — — — — 4,611 4,611 On acquisition (Refer Note (4(a),(b),(c)) 8,263 59,478 — 649 6,090 — 9,066 400 1,287 85,233 Translation adjustments 1,952 (703 ) (589 ) 4 41 — 59 — (72 ) 692 Balance as at March 31, 2017 $ 167,001 $ 121,922 $ 3,861 $ 653 $ 6,131 $ 1,835 $ 9,451 $ 400 $ 25,586 $ 336,840 Accumulated amortization Balance as at April 1, 2016 $ 145,483 $ 58,992 $ 4,450 $ — $ — $ 1,835 $ 326 $ — $ 8,101 $ 219,187 Amortization 10,653 4,016 — 78 167 — 650 — 4,975 20,539 Translation adjustments 1,840 (833 ) (589 ) 2 5 — (12 ) — 77 490 Balance as at March 31, 2017 $ 157,976 $ 62,175 $ 3,861 $ 80 $ 172 $ 1,835 $ 964 $ — $ 13,153 $ 240,216 Net carrying value as at March 31, 2017 $ 9,025 $ 59,747 $ — $ 573 $ 5,959 $ — $ 8,487 $ 400 $ 12,433 $ 96,624 The changes in the carrying value of intangible assets for the year ended March 31, 2018 are as follows: Gross carrying value Customer contracts Customer relationships Intellectual Property and other rights Trade names Technology Leasehold benefits Covenant not-to- compete Service mark Software Total Balance as at April 1, 2017 $ 167,001 $ 121,922 $ 3,861 $ 653 $ 6,131 $ 1,835 $ 9,451 400 $ 25,586 $ 336,840 Additions — — 250 — — — — — 7,369 7,619 Translation adjustments 93 940 470 — (6 ) — 10 — 894 2,401 Balance as at March 31, 2018 $ 167,094 $ 122,862 $ 4,581 $ 653 $ 6,125 $ 1,835 $ 9,461 $ 400 $ 33,849 $ 346,860 Accumulated amortization Balance as at April 1, 2017 $ 157,976 $ 62,175 $ 3,861 $ 80 $ 172 $ 1,835 $ 964 $ — $ 13,153 $ 240,216 Amortization 2,725 3,700 74 236 790 — 2,310 — 5,670 15,505 Translation adjustments (62 ) 873 470 (1 ) (4 ) — 12 — 199 1,487 Balance as at March 31, 2018 $ 160,639 $ 66,748 $ 4,405 $ 315 $ 958 $ 1,835 $ 3,286 $ — $ 19,022 $ 257,208 Net carrying value as at March 31, 2018 $ 6,455 $ 56,114 $ 176 $ 338 $ 5,167 $ — $ 6,175 $ 400 $ 14,827 $ 89,652
Estimated Remaining Weighted Average Amortization Periods for Definite Lived Intangible Assets	As at March 31, 2018, the estimated remaining weighted average amortization periods for definite lived intangible assets are as follows: Balance life (In months) Customer contracts 29 Customer relationships 196 Covenant not-to-compete 33 Trade names 21 Technology 80 Intellectual Property and other rights 17 Software 24
Estimated Annual Amortization Expense	The estimated annual amortization expense based on remaining weighted average amortization periods for intangible assets and exchange rates, each as at March 31, 2018 are as follows: Amount 2019 $ 15,279 2020 14,204 2021 9,700 2022 6,095 2023 5,047 Thereafter 38,927 $ 89,252 * * excludes service mark, as it has an indefinite useful life

Property and equipment (Tables)

Property and equipment (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Changes in Carrying Value of Property and Equipment	The changes in the carrying value of property and equipment for the year ended March 31, 2017 are as follows: Gross carrying value Buildings Computers and software Furniture, fixtures and office equipment Vehicles Leasehold improvements Total Balance as at April 1, 2016 $ 10,150 $ 69,203 $ 60,860 $ 459 $ 52,589 $ 193,261 Additions — 4,411 7,455 135 8,105 20,106 On acquisition (Refer Note 4(a),(b),(c)) — 1,014 1,895 14 1,820 4,743 Disposals/retirements — (3,407 ) (1,619 ) (33 ) (1,723 ) (6,782 ) Translation adjustments 96 (1,350 ) 286 12 201 (755 ) Balance as at March 31, 2017 $ 10,246 $ 69,871 $ 68,877 $ 587 $ 60,992 $ 210,573 Accumulated depreciation Balance as at April 1, 2016 $ 3,661 $ 58,768 $ 47,375 $ 347 $ 36,874 $ 147,025 Depreciation 505 5,742 5,126 92 5,438 16,903 Disposals/retirements — (3,327 ) (1,241 ) (20 ) (1,354 ) (5,942 ) Translation adjustments 42 (1,372 ) 171 10 222 (927 ) Balance as at March 31, 2017 $ 4,208 $ 59,811 $ 51,431 $ 429 $ 41,180 $ 157,059 Capital work-in-progress 1,282 Net carrying value as at March 31, 2017 $ 54,796 The changes in the carrying value of property and equipment for the year ended March 31, 2018 are as follows: Gross carrying value Buildings Computers and software Furniture, fixtures and office equipment Vehicles Leasehold improvements Total Balance as at April 1, 2017 $ 10,246 $ 69,871 $ 68,877 $ 587 $ 60,992 $ 210,573 Additions — 4,597 9,389 93 9,756 23,835 Disposals/retirements — (3,350 ) (1,718 ) (29 ) (2,303 ) (7,400 ) Translation adjustments (23 ) 1,965 839 5 721 3,507 Balance as at March 31, 2018 $ 10,223 $ 73,083 $ 77,387 $ 656 $ 69,166 $ 230,515 Accumulated depreciation Balance as at April 1, 2017 $ 4,208 $ 59,811 $ 51,431 $ 429 $ 41,180 $ 157,059 Depreciation 514 6,442 6,623 97 6,278 19,954 Disposals/retirements — (3,345 ) (1,674 ) (30 ) (2,308 ) (7,357 ) Translation adjustments (12 ) 1,822 512 1 296 2,619 Balance as at March 31, 2018 $ 4,710 $ 64,730 $ 56,892 $ 497 $ 45,446 $ 172,275 Capital work-in-progress 2,366 Net carrying value as at March 31, 2018 $ 60,606

Loans and borrowings (Tables)

Loans and borrowings (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Long-term Loans and Borrowings	The long-term loans and borrowings consist of the following: As at March 31, 2018 March 31, 2017 Currency Interest rate Final maturity ( fiscal year) Foreign currency Total Foreign currency Total US dollars 3M USD Libor +1.27% 2020 $ — 22,700 — 34,000 US dollars 3M USD Libor +0.95% 2022 $ — 67,200 — 84,000 Total 89,900 118,000 Less: Debt issuance cost 769 1,257 Total 89,131 116,743 Current portion of long term debt $ 27,740 $ 27,613 Long term debt $ 61,391 $ 89,130

Financial instruments (Tables)

Financial instruments (Tables)	12 Months Ended
	Mar. 31, 2018
Carrying Value and Fair Value of Financial Instruments by Class	The carrying value and fair value of financial instruments by class as at March 31, 2018 are as follows: Financial assets Loans and receivables Financial assets at FVTPL Derivative designated as cash flow hedges (carried at fair value) Available for sale Total carrying value Total fair value Cash and cash equivalents $ 99,829 $ — $ — $ — $ 99,829 $ 99,829 Investment in fixed deposits 21,548 — — — 21,548 21,548 Investments in marketable securities and mutual funds — — — 99,954 99,954 99,954 Trade receivables 71,388 — — — 71,388 71,388 Unbilled revenue 61,721 — — — 61,721 61,721 Funds held for clients 10,066 — — — 10,066 10,066 Prepayments and other assets (1) 4,410 — — — 4,410 4,410 Other non-current (2) 10,243 — — — 10,243 10,243 Derivative assets — 2,212 12,771 — 14,983 14,983 Total carrying value $ 279,205 $ 2,212 $ 12,771 $ 99,954 $ 394,142 $ 394,142 Financial liabilities Financial liabilities at FVTPL Derivative designated as cash flow hedges (carried at fair value) Financial liabilities at amortized cost Total carrying value Total fair value Trade payables $ — $ — $ 19,703 $ 19,703 $ 19,703 Long term debt (includes current portion) (3) — — 89,900 89,900 89,900 Other employee obligations (4) — — 59,346 59,346 59,346 Provision and accrued expenses — — 28,826 28,826 28,826 Other liabilities (5) 11,388 — 2,447 13,835 13,835 Derivative liabilities 946 7,809 — 8,755 8,755 Total carrying value $ 12,334 $ 7,809 $ 200,222 $ 220,365 $ 220,365 Notes: (1) Excluding non-financial (2) Excluding non-financial (3) Excluding non-financial (4) Excluding non-financial (5) Excluding non-financial The carrying value and fair value of financial instruments by class as at March 31, 2017 are as follows: Financial assets Loans and receivables Financial assets at FVTPL Derivative designated as cash flow hedges (carried at fair value) Available for sale Total carrying value Total fair value Cash and cash equivalents $ 69,803 $ — $ — $ — $ 69,803 $ 69,803 Investment in fixed deposits 24,673 — — — 24,673 24,673 Investments in marketable securities and mutual funds — — — 87,652 87,652 87,652 Investment in FMPs — 96 — — 96 96 Trade receivables 60,423 — — — 60,423 60,423 Unbilled revenue 48,915 — — — 48,915 48,915 Funds held for clients 9,135 — — — 9,135 9,135 Prepayments and other assets (1) 4,262 — — — 4,262 4,262 Other non-current (2) 10,791 — — — 10,791 10,791 Derivative assets — 5,041 36,941 — 41,982 41,982 Total carrying value $ 228,002 $ 5,137 $ 36,941 $ 87,652 $ 357,732 $ 357,732 Financial liabilities Financial liabilities at FVTPL Derivative designated as cash flow hedges (carried at fair value) Financial liabilities at amortized cost Total carrying value Total fair value Trade payables $ — $ — $ 14,239 $ 14,239 $ 14,239 Long term debt (includes current portion) (3) — — 118,000 118,000 118,000 Other employee obligations (4) — — 46,701 46,701 46,701 Provision and accrued expenses — — 27,217 27,217 27,217 Other liabilities (5) 19,678 — 1,086 20,764 20,764 Derivative liabilities 26 4,757 — 4,783 4,783 Total carrying value $ 19,704 $ 4,757 $ 207,243 $ 231,704 $ 231,704 Notes: (1) Excluding non-financial (2) Excluding non-financial (3) Excluding non-financial (4) Excluding non-financial (5) Excluding non-financial
Financial Assets and Liabilities Subject to Offsetting, Enforceable Master Netting Arrangements or Similar Agreements	Financial assets and liabilities subject to offsetting, enforceable master netting arrangements or similar agreements as at March 31, 2018 are as follows: Description of types of financial assets Gross amounts of recognized financial assets Gross amounts of recognized financial liabilities offset in the statement of financial position Net amounts of financial assets presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral received Derivative assets $ 14,983 $ — $ 14,983 $ (4,215 ) $ — $ 10,768 Total $ 14,983 $ — $ 14,983 $ (4,215 ) $ — $ 10,768 Description of types of financial liabilities Gross amounts of recognized financial liabilities Gross amounts of recognized financial assets offset in the statement of financial position Net amounts of financial liabilities presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral pledged Derivative liabilities $ 8,755 $ — $ 8,755 $ (4,215 ) $ — $ 4,540 Total $ 8,755 $ — $ 8,755 $ (4,215 ) $ — $ 4,540 Financial assets and liabilities subject to offsetting, enforceable master netting arrangements or similar agreements as at March 31, 2017 are as follows: Description of types of financial assets Gross amounts of recognized financial assets Gross amounts of recognized financial liabilities offset in the statement of financial position Net amounts of financial assets presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral received Derivative assets $ 41,982 $ — $ 41,982 $ (1,712 ) $ — $ 40,270 Total $ 41,982 $ — $ 41,982 $ (1,712 ) $ — $ 40,270 Description of types of financial liabilities Gross amounts of recognized financial liabilities Gross amounts of recognized financial assets offset in the statement of financial position Net amounts of financial liabilities presented in the statement of financial position Related amount not set off in financial instruments Net Amount Financial instruments Cash collateral pledged Derivative liabilities $ 4,783 $ — $ 4,783 $ (1,712 ) $ — $ 3,071 Total $ 4,783 $ — $ 4,783 $ (1,712 ) $ — $ 3,071
Assets and Liabilities Measured at Fair Value on Recurring Basis	The assets and liabilities measured at fair value on a recurring basis as at March 31, 2018 are as follows:- Fair value measurement at reporting date using Description March 31, 2018 Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Assets Financial assets at FVTPL Foreign exchange contracts $ 2,212 $ — $ 2,212 $ — Financial assets at fair value through other comprehensive income Foreign exchange contracts 11,709 — 11,709 — Interest rate swaps 1,062 — 1,062 — Investments in marketable securities and mutual funds 99,954 99,412 542 — Total assets $ 114,937 $ 99,412 $ 15,525 $ — Liabilities Financial liabilities at FVTPL Foreign exchange contracts $ 946 $ — $ 946 $ — Contingent consideration 11,388 — — 11,388 Financial liabilities at fair value through other comprehensive income Foreign exchange contracts 7,809 — 7,809 — Total liabilities $ 20,143 $ — $ 8,755 $ 11,388 The assets and liabilities measured at fair value on a recurring basis as at March 31, 2017 are as follows:- Fair value measurement at reporting date using Description March 31, 2017 Quoted prices in active markets for identical assets (Level 1) Significant other observable inputs (Level 2) Significant unobservable inputs (Level 3) Assets Financial assets at FVTPL Foreign exchange contracts $ 5,041 $ — $ 5,041 $ — Investment in FMPs 96 96 — — Financial assets at fair value through other comprehensive income Foreign exchange contracts 36,733 — 36,733 — Interest rate swaps 208 — 208 — Investments in marketable securities and mutual funds 87,652 87,223 429 — Total assets $ 129,730 $ 87,319 $ 42,411 $ — Liabilities Financial liabilities at FVTPL Foreign exchange contracts $ 26 $ — $ 26 $ — Contingent consideration 19,678 — — 19,678 Financial liabilities at fair value through other comprehensive income Foreign exchange contracts 4,136 — 4,136 — Interest rate swaps 621 — 621 — Total liabilities $ 24,461 $ — $ 4,783 $ 19,678
Summary of Contingent Consideration Categorized Under Level 3 Fair Value Measurement	The movement in contingent consideration categorized under Level 3 fair value measurement is given below: For the year ended March 31, 2018 March 31, 2017 Balance at the beginning of the year $ 19,678 $ — Additions — 19,934 Payouts (7,000 ) — Gain recognized in the consolidated statement of income (1,553 ) (279 ) Finance expense recognized in the consolidated statement of income 263 23 Balance at the end of the year 11,388 19,678
Notional Values of Outstanding Foreign Exchange Forward Contracts, Foreign Exchange Option Contracts and Interest Rate Swap Contracts	The following table presents the notional values of outstanding foreign exchange forward contracts, foreign exchange option contracts and interest rate swap contracts: As at March 31, 2018 March 31, 2017 Forward contracts (Sell) In US dollars $ 242,418 $ 241,673 In United Kingdom Pound Sterling 132,591 126,441 In Euro 23,883 14,769 In Australian dollars 48,147 43,474 Others 2,332 3,511 $ 449,371 $ 429,868 Option contracts (Sell) In US dollars $ 107,629 $ 84,490 In United Kingdom Pound Sterling 116,401 94,094 In Euro 21,483 14,494 In Australian dollars 28,828 19,412 Others 927 1,978 $ 275,268 $ 214,468 Interest Rate Swap contracts In US dollars 89,900 118,000
Gain/(Loss) Reclassified from Other Comprehensive Income into Consolidated Statement of Income	The amount of gain/ (loss) reclassified from other comprehensive income into consolidated statement of income in respective line items for the years ended March 31, 2018, 2017 and 2016 are as follows: Year ended March 31, 2018 2017 2016 Revenue $ 11,231 $ 7,952 $ 7,941 Foreign exchange gain, net 15,766 16,896 6,281 Finance expense (561 ) (71 ) — Income tax related to amounts reclassified into consolidated statement of income (9,965 ) (8,998 ) (5,230 ) Total $ 16,471 $ 15,779 $ 8,992
Percentage of Revenue Generated from Top Customer and Top Five Customers	The following table gives details in respect of the percentage of revenue generated from the Company’s top customer and top five customers: Year Ended March 31, 2018 2017 2016 Revenue from top customer 6.8 % 9.0 % 10.9 % Revenue from top five customers 29.4 % 32.1 % 30.7 %
Contractual Maturities of Financial Liabilities	The contractual maturities of financial liabilities are as follows: As at March 31, 2018 Less than 1 Year 1-2 years 2-5 years Total Long term debt (includes current portion) (1) $ 28,100 $ 28,200 $ 33,600 $ 89,900 Trade payables 19,703 — — 19,703 Provision and accrued expenses 28,826 — — 28,826 Other liabilities 10,680 3,154 — 13,834 Other employee obligations 59,347 — — 59,347 Derivative financial instruments 6,466 2,289 — 8,755 Total (2) $ 153,122 $ 33,643 $ 33,600 $ 220,365 Notes: (1) Before netting off debt issuance cost of $769. (2) Non-financial As at March 31, 2017 Less than 1 Year 1-2 years 2-5 years Total Long term debt (includes current portion) (1) $ 28,100 $ 28,100 $ 61,800 $ 118,000 Trade payables 14,239 — — 14,239 Provision and accrued expenses 27,217 — — 27,217 Other liabilities 9,338 8,195 3,231 20,764 Other employee obligations 46,701 — — 46,701 Derivative financial instruments 3,947 836 — 4,783 Total (2) $ 129,542 $ 37,131 $ 65,031 $ 231,704 Notes: (1) Before netting off debt issuance cost of $1,257. (2) Non-financial
Summary of Net Cash Position	The balanced view of liquidity and financial indebtedness is stated in the table below. This calculation of the net cash position is used by the management: As at March 31, 2018 March 31, 2017 Cash and cash equivalents $ 99,829 $ 69,803 Investments 121,502 112,421 Long term debt (includes current portion) (1) (89,900 ) (118,000 ) Net cash position $ 131,431 $ 64,224 Note: (1) Before netting off debt issuance cost of $769 and $1,257 as at March 31, 2018 and March 31, 2017, respectively.
Currency risk [member]
Foreign Currency Risk from Non-derivative Financial Instruments	The foreign currency risk from non-derivative As at March 31, 2018 US Dollar Pound Sterling Indian Rupees Australian Dollar Euro Other currencies Total Cash and cash equivalents $ 399 4,735 — 2,991 339 610 9,074 Trade receivables 100,002 46,658 3,850 24,686 7,289 2,525 185,010 Unbilled revenue 7,178 3,209 — 643 6,230 858 18,118 Prepayments and other current assets 428 188 10 29 63 11 729 Other non-current 3 — — — — 16 19 Trade payables (27,613 ) (64,070 ) (6,989 ) (16,093 ) (1,429 ) (19 ) (116,213 ) Provisions and accrued expenses (2,314 ) (291 ) (205 ) — (154 ) (19 ) (2,983 ) Pension and other employee obligations (134 ) — — — (12 ) (306 ) (452 ) Other liabilities (7 ) (4 ) — — — — (11 ) Net assets/ (liabilities) $ 77,942 (9,575 ) (3,334 ) 12,256 12,325 3,676 93,291 The foreign currency risk from non-derivative As at March 31, 2017 US Dollar Pound Sterling Indian Rupees Australian Dollar Euro Other currencies Total Cash and cash equivalents $ 599 253 — 2,606 1,323 35 4,816 Trade receivables 98,713 53,668 2,996 23,373 5,370 3,192 187,312 Unbilled revenue 4,656 1,241 3,062 3,205 494 12,658 Prepayments and other current assets 428 130 3 66 30 14 671 Other non-current 3 — — — — 16 19 Trade payables (40,600 ) (71,039 ) (3,986 ) (19,205 ) (1,140 ) (312 ) (136,282 ) Provisions and accrued expenses (1,706 ) (504 ) (105 ) (128 ) (68 ) (208 ) (2,719 ) Pension and other employee obligations (56 ) — — — (31 ) (165 ) (252 ) Other liabilities (5 ) (2 ) — — — 14 7 Net assets/ (liabilities) $ 62,032 (16,253 ) (1,092 ) 9,774 8,689 3,080 66,230
Trade receivables [member]
Age-wise Break-up of Trade Receivables, Net of Allowances that are Past Due Beyond Credit Period	The age-wise As at March 31, 2018 March 31, 2017 Neither past due nor impaired $ 56,372 $ 45,939 Past due but not impaired Past due 0-30 9,578 8,260 Past due 31-60 2,738 2,544 Past due 61-90 834 1,174 Past due over 90 days 1,866 2,506 Past due and impaired 564 1,713 Total $ 71,952 $ 62,136 Allowances for doubtful trade receivables $ (564 ) $ (1,713 ) Trade receivables, net of allowances for doubtful receivables $ 71,388 $ 60,423

Pension and other employee ob49

Pension and other employee obligations (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Pension and Other Employee Obligations	Pension and other employee obligations consist of the following: As at March 31, 2018 March 31, 2017 Current: Salaries and bonus $ 59,346 $ 46,701 Pension 1,189 770 Withholding taxes on salary and statutory payables 4,082 5,462 Total $ 64,617 $ 52,933 Non-current: Pension and other obligations $ 9,621 $ 10,680 Total $ 9,621 $ 10,680
Summary of Employee Benefit Costs	Employee benefit costs consist of the following: Year ended March 31, 2018 2017 2016 Salaries and bonus $ 405,665 $ 307,378 $ 272,017 Employee benefit plans: Defined contribution plan 11,684 10,265 7,458 Defined benefit plan 3,042 2,639 2,184 Share-based compensation expense (Refer Note 22) 30,565 23,036 17,919 Total $ 450,956 $ 343,318 $ 299,578 Employee benefit costs is recognized in the following line items in the consolidated statement of income: Year ended March 31, 2018 2017 2016 Cost of revenue $ 329,289 $ 249,701 $ 217,098 Selling and marketing expenses 31,373 24,717 22,336 General and administrative expenses 90,294 68,900 60,144 Total $ 450,956 $ 343,318 $ 299,578
Contributions to Defined Contribution Plans	The Company’s contributions to defined contribution plans are as follows: Year ended March 31, 2018 2017 2016 India $ 8,123 $ 7,587 $ 5,173 Philippines 127 106 83 South Africa 860 715 617 Sri Lanka 625 661 612 United Kingdom 670 780 681 United States 1,279 416 292 Total 11,684 10,265 7,458
Summary of Net Periodic Cost	The net periodic cost recognized by the Company in respect of gratuity payments under the Company’s gratuity plans covering eligible employees of the Company in India, the Philippines and Sri Lanka is as follows: Year ended March 31, 2018 2017 2016 Service cost $ 1,917 $ 2,188 $ 1,765 Past service cost 538 — — Interest on the net defined benefit liability 587 451 419 Net gratuity cost $ 3,042 $ 2,639 $ 2,184
Summary of Net Defined Benefit Liability (Asset)	As at March 2018 March 2017 Change in projected benefit obligations Obligation at beginning of the year $ 11,776 $ 8,450 Foreign currency translation (118 ) (30 ) Service cost 1,917 2,188 Past service cost 538 — Interest cost 657 513 Business combinations — 95 Benefits paid (1,160 ) (1,283 ) Actuarial (gain)/loss From changes in demographic assumptions 62 463 From changes in financial assumptions (3,428 ) (126 ) From actual experience compared to assumptions 857 1,506 Benefit obligation at end of the year $ 11,101 $ 11,776 Change in plan assets Plan assets at beginning of the year $ 976 $ 849 Foreign currency translation (5 ) 22 Expected return on plan assets 70 62 Actuarial (loss) /gain (23 ) 39 Actual contributions 1,104 1,148 Benefits paid (1,081 ) (1,144 ) Plan assets at end of the year $ 1,041 $ 976 Accrued pension liability Current $ 1,189 $ 770 Non-current 8,871 10,030 Net amount recognized $ 10,060 $ 10,800 Present value of funded defined benefit obligation $ 10,418 $ 8,766 Fair value of plan assets (1,041 ) (976 ) 9,377 7,790 Present value of unfunded defined benefit obligation $ 683 $ 3,010 Weighted average duration of defined benefit obligation (both funded and unfunded) 4.8 years 8.3 years
Actuarial Assumptions For Gratuity Plans	The assumptions used in accounting for the gratuity plans are as follows: Year ended March 31, 2018 2017 2016 Discount rate: India 6.6% to 7.3% 7.05% 7.35% Philippines 3.1% 5.45% 4.75% Sri Lanka 10.0% 12.8% 12.30% Rate of increase in compensation level 7% to 10% 7% to 15% 6% to 8% Expected rate of return on plan assets 7.3% 7.05% 7.35%
Sensitivity of Defined Benefit Obligation to a Change in Each Significant Actuarial Assumption	As at March 31, 2018, for each of the Company’s defined benefit plans, the sensitivity of the defined benefit obligation to a change in each significant actuarial assumption is as follows: India Philippines Sri Lanka Discount rate: Increase in discount rate by 1% (7.3)% (1.4 )% (3.4 )% Decrease in discount rate by 1% 0.7% 1.5 % 0.5 % Rate of increase in compensation level: Increase in salary escalation rate by 1% 3.6% 1.0 % 1.5 % Decrease in salary escalation rate by 1% (3.5)% (0.9 )% (1.5 )%
Maturity Analysis of Defined Benefit Payments	The maturity analysis of the Company’s defined benefit payments is as follows: Amount 2019 $ 2,230 2020 2,194 2021 2,179 2022 2,245 2023 2,370 Thereafter 9,260 $ 20,478

Provisions and accrued expens50

Provisions and accrued expenses (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Provisions and Accrued Expenses	Provisions and accrued expenses consist of the following: As at March 31, 2018 March 31, 2017 Accrued expenses 28,826 27,217 Total $ 28,826 $ 27,217

Deferred revenue (Tables)

Deferred revenue (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Deferred Revenue	Deferred revenue consists of the following: As at March 31, 2018 March 31, 2017 Current: Payments in advance of services $ 557 $ 717 Advance billings 2,104 4,014 Others 247 747 Total $ 2,908 $ 5,478 Non-current: Payments in advance of services $ 550 $ 359 Advance billings 2 — Others 19 19 Total $ 571 $ 378

Other liabilities (Tables)

Other liabilities (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Other Liabilities	Other liabilities consist of the following: As at March 31, 2018 March 31, 2017 Current: Withholding taxes and value added tax payables $ 5,117 $ 5,356 Contingent consideration (Refer note 4(a), 4(b) and 4(c)) 8,233 8,252 Deferred rent 800 677 Other liabilities 1,589 1,730 Total $ 15,739 $ 16,015 Non-current: Deferred rent $ 6,544 $ 5,292 Contingent consideration (Refer note 4(a), 4(b) and 4(c)) 3,155 11,426 Other liabilities 1,963 1,751 Total $ 11,662 $ 18,469

Expenses by nature (Tables)

Expenses by nature (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Expenses by Nature	Expenses by nature consist of the following: Year ended March 31, 2018 2017 2016 Employee cost $ 450,956 $ 343,318 $ 299,578 Repair payments 16,970 24,102 31,170 Facilities cost 89,037 75,383 67,689 Depreciation 19,954 16,903 15,435 Legal and professional expenses 22,972 15,902 13,227 Travel expenses 23,748 18,563 17,972 Others 38,886 33,526 30,035 Total cost of revenue, selling and marketing and general and administrative expenses $ 662,523 $ 527,697 $ 475,106

Finance expense (Tables)

Finance expense (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Finance Expense	Finance expense consists of the following: Year ended March 31, 2018 2017 2016 Interest expense $ 3,215 $ 424 $ 265 Interest rate swaps 561 71 — Debt issue cost 488 52 13 Total $ 4,264 $ 547 $ 278

Other income, net (Tables)

Other income, net (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Other Income, Net	Other income, net consists of the following: Year ended March 31, 2018 2017 2016 Interest income $ 3,693 $ 2,083 $ 1,197 Dividend income 3,570 4,131 5,039 Net gain arising on financial assets designated as FVTPL 3 6 41 Others, net 3,964 2,469 2,217 Total $ 11,230 $ 8,689 $ 8,494

Share-based payments (Tables)

Share-based payments (Tables)	12 Months Ended
	Mar. 31, 2018
Summary of Share-based Compensation Expense	Share-based compensation expense during the years ended March 31, 2018, 2017 and 2016 are as follows: Year ended March 31, 2018 2017 2016 Share-based compensation expense recorded in $ $ $ Cost of revenue 3,770 2,765 1,923 Selling and marketing expenses 2,557 1,723 1,370 General and administrative expenses 24,238 18,548 14,626 Total share-based compensation expense $ 30,565 $ 23,036 $ 17,919
Movements in Number of Options Outstanding under 2006 Incentive Award Plan and Related Weighted Average Exercise Prices	Movements in the number of options outstanding under the 2006 Incentive Award Plan and their related weighted average exercise prices are as follow: Shares Weighted average exercise price Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 739,618 $ 23.34 0.54 $ 5,419 Exercised (425,941 ) 10.52 Lapsed (196,498 ) 13.44 Outstanding as at March 31, 2017 117,179 $ 27.25 0.10 $ 163 Exercised (48,227 ) 7.63 Lapsed (68,952 ) 7.87 Outstanding as at March 31, 2018 — — — — Options exercisable — $ — — $ —
RSUs dependent on non-market performance condition [member]
Movements in Number of Shares Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values	(i) Movements in the number of RSUs dependent on non-market Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 1,448,312 $ 19.25 7.78 $ 44,376 Granted 516,264 30.26 Exercised (343,623 ) 20.18 Forfeited (47,707 ) 25.50 Lapsed — — Outstanding as at March 31, 2017 1,573,246 $ 22.47 7.50 $ 45,011 Granted 497,689 30.85 Exercised (961,111 ) 21.45 Forfeited (34,775 ) 29.07 Lapsed (2,216 ) 23.47 Outstanding as at March 31, 2018 1,072,833 $ 27.05 7.75 $ 48,632 RSUs exercisable 309,312 $ 20.90 5.94 $ 14,021
RSUs dependent on market performance condition [member]
Movements in Number of Shares Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values	Movements in the number of RSUs dependent on market performance condition outstanding under the 2006 Incentive Award Plan and the 2016 Incentive Award Plan and their related weighted average fair values are as follows: Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 129,590 $ 4.44 8.53 $ 3,971 Granted 74,400 12.56 Exercised — — Forfeited — — Lapsed — — Outstanding as at March 31, 2017 203,990 $ 13.21 8.10 $ 5,836 Granted — Exercised — Forfeited — Lapsed — Outstanding as at March 31, 2018 203,990 13.21 7.10 $ 9,247 RSUs exercisable — $ — — $ —
RSUs related total shareholders return [member]
Movements in Number of Shares Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values	Movements in the number of RSUs linked to the TSR condition outstanding under the 2016 Incentive Award Plan and their related weighted average fair values are as follows: Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2017 — $ — — $ — Granted 248,655 36.52 Exercised — Forfeited — Lapsed — Outstanding as at March 31, 2018 248,655 36.52 9.08 11,272 RSUs exercisable — $ — — $ —
PSUs [member]
Movements in Number of Shares Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values	Movements in the number of PSUs outstanding under the 2006 Incentive Award Plan and the 2016 Incentive Award Plan and their related weighted average fair values are as follow: Shares Weighted average fair value Weighted average remaining contract term (in years) Aggregate intrinsic value Outstanding as at March 31, 2016 951,588 $ 17.83 7.77 $ 29,157 Granted 422,062 31.12 Exercised (141,741 ) 14.11 Forfeited (47,057 ) 26.27 Outstanding as at March 31, 2017 1,184,852 $ 21.00 7.36 $ 33,899 Granted 400,463 30.35 Exercised (506,660 ) 16.79 Forfeited (18,681 ) 29.38 Outstanding as at March 31, 2018 1,059,975 26.36 7.51 48,048 PSUs exercisable 194,629 $ 18.14 5.86 $ 8,823

Income taxes (Tables)

Income taxes (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Domestic and Foreign Source Component of Profit/(Loss) Before Income Taxes	The domestic and foreign source component of profit / (loss) before income taxes is as follows: Year ended March 31, 2018 2017 2016 Domestic $ (4,439 ) $ (5,342 ) $ (4,121 ) Foreign 106,306 60,635 85,181 Profit before income taxes $ 101,867 $ 55,293 $ 81,060
Provision for Income Taxes	The Company’s provision for income taxes consists of the following: Year ended March 31, 2018 2017 2016 Current taxes Domestic taxes $ — $ — $ — Foreign taxes 24,494 25,785 19,615 24,494 25,785 19,615 Deferred taxes Domestic taxes — — — Foreign taxes (9,063 ) (8,255 ) 1,565 (9,063 ) (8,255 ) 1,565 Provision for income taxes $ 15,431 $ 17,530 $ 21,180
Income Taxes Recognized Directly in Equity	Income taxes recognized directly in equity are as follows: Year ended March 31, 2018 2017 2016 Current taxes: Excess tax deductions related to share-based payments (685 ) (270 ) (229 ) $ (685 ) $ (270 ) $ (229 ) Deferred taxes: Excess tax deductions related to share-based payments (1,135 ) 715 (688 ) $ (1,135 ) $ 715 $ (688 ) Total income tax recognized directly in equity $ (1,820 ) $ 445 $ (917 )
Income Taxes Recognized in Other Comprehensive Income	Income taxes recognized in other comprehensive income are as follows: Year ended March 31, 2018 2017 2016 Current taxes — — — Deferred taxes: Unrealized gain/(loss) on cash flow hedging derivatives (9,409 ) 6,921 (4,259 ) Total income tax recognized directly in other comprehensive income $ (9,409 ) $ 6,921 $ (4,259 )
Reconciliation of Estimated Income Tax to Provision for Income Taxes	The reconciliation of estimated income tax to provision for income taxes: Year ended March 31, 2018 2017 2016 Profit before income taxes $ 101,867 $ 55,293 $ 81,060 Income tax expense at tax rates applicable to individual entities 32,702 21,765 28,067 Effect of: Items not deductible for tax 221 455 771 Exempt income (11,250 ) (7,706 ) (6,845 ) Non tax deductible goodwill impairment — 4,335 — (Gain)/Loss in respect of which deferred tax (liability)/asset not recognized due to uncertainty and ineligibility to carry forward 324 (105 ) 259 Recognition of unutilized tax benefits / Unrecognized losses utilized — (1,220 ) (294 ) Temporary difference that will reverse during tax holiday period 22 1,580 30 Change in tax rate and law (5,685 ) 78 (152 ) Provision for uncertain tax position — (1,499 ) 2 State taxes 317 14 12 Due to acquisitions and merger (1,686 ) — — One time tax on undistributed earnings 266 — — Others, net 200 (167 ) (670 ) Provision for income taxes $ 15,431 $ 17,530 $ 21,180
Summary of Deferred Taxes Arising from Temporary Differences and Unused Tax Losses	Deferred taxes for the year ended March 31, 2017 arising from temporary differences and unused tax losses can be summarized below: Opening balance Additions due to acquisition during the year Recognized in statement of income Recognized in equity Recognized in/ Reclassified from other comprehensive income Foreign currency translation Closing balance Deferred tax assets: Property and equipment $ 5,512 $ (873 ) $ 932 $ — $ — $ 77 $ 5,648 Net operating loss carry forward 3,684 — 2,026 — — 12 5,722 Accruals deductible on actual payment 5,352 70 (1 ) — — 220 5,641 Share-based compensation expense 11,008 — 1,781 (715 ) — 190 12,264 Minimum alternate tax 68 — 96 — — 3 167 Others 362 — 679 — — (66 ) 975 Total deferred tax assets $ 25,986 $ (803 ) $ 5,513 $ (715 ) $ — $ 436 $ 30,417 Deferred tax liabilities: Intangibles (712 ) 24,577 (2,769 ) — — 27 21,123 Unrealized gain/(loss) on cash flow hedging and investments 4,857 — 27 — 6,921 489 12,294 Others 1,108 — — — — 5 1,113 Total deferred tax liabilities $ 5,253 $ 24,577 $ (2,742 ) $ — $ 6,921 $ 521 $ 34,530 Net deferred tax assets/(liabilities) $ 20,733 $ (25,380 ) $ 8,255 $ (715 ) $ (6,921 ) $ (85 ) $ (4,113 ) Deferred taxes for the year ended March 31, 2016 arising from temporary differences and unused tax losses can be summarized below: Opening balance Additions due to acquisition during the year Recognized in statement of income Recognized in equity Recognized in/ Reclassified from other comprehensive income Foreign currency translation Closing balance Deferred tax assets: Property and equipment $ 6,538 $ — $ (724 ) $ — $ — $ (302 ) $ 5,512 Net operating loss carry forward 4,304 — (448 ) — — (172 ) 3,684 Accruals deductible on actual payment 4,201 — 1,443 — — (292 ) 5,352 Share-based compensation expense 6,110 — 4,480 688 — (270 ) 11,008 Minimum alternate tax 8,327 — (7,941 ) — — (318 ) 68 Others 1,444 — (1,179 ) — — 97 362 Total deferred tax assets $ 30,924 $ — $ (4,369 ) $ 688 $ — $ (1,257 ) $ 25,986 Deferred tax liabilities: Intangibles 2,045 837 (3,477 ) — — (118 ) (712 ) Unrealized gain/(loss) on cash flow hedging and investments 9,821 — (436 ) — (4,259 ) (269 ) 4,857 Others — — 1,108 — — — 1,108 Total deferred tax liabilities $ 11,866 $ 837 $ (2,804 ) $ — $ (4,259 ) $ (387 ) $ 5,253 Net deferred tax assets/(liabilities) $ 19,058 $ (837 ) $ (1,565 ) $ 688 $ 4,259 $ (870 ) $ 20,733
Deferred Tax Presented in Statement of Financial Position	Deferred tax presented in the statement of financial position is as follows: As at March 31, 2018 March 31, 2017 Deferred tax assets 27,395 16,687 Deferred tax liabilities (11,812 ) (20,800 ) Net deferred tax assets $ 15,583 $ (4,113 )

Earnings per share (Tables)

Earnings per share (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Computation of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share: Year ended March 31, 2018 2017 2016 Numerator: Profit $ 86,436 $ 37,763 $ 59,880 Denominator: Basic weighted average ordinary shares outstanding 50,388,440 50,582,852 51,372,117 Dilutive impact of equivalent stock options and RSUs 2,527,160 2,357,456 2,267,553 Diluted weighted average ordinary shares outstanding 52,915,600 52,940,308 53,639,670

Related party (Tables)

Related party (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
List of the Company's Subsidiaries	The following is a list of the Company’s subsidiaries as at March 31, 2018: Direct subsidiaries Step subsidiaries Place of incorporation WNS Global Services Netherlands Cooperatief U.A. The Netherlands WNS Global Services Philippines Inc. Philippines WNS Global Services (Romania) S.R.L. Romania WNS North America Inc. Delaware, USA WNS Business Consulting Services Private Limited India WNS Global Services Inc. Delaware, USA WNS BPO Services Costa Rica, S.R.L Costa Rica Denali Sourcing Services Inc. (1) Delaware, USA WNS Assistance Limited (previously WNS Workflow Technologies Limited) United Kingdom WNS Assistance (Legal) Limited (5) United Kingdom Accidents Happen Assistance Limited United Kingdom WNS Legal Assistance LLP (6) United Kingdom WNS (Mauritius) Limited Mauritius WNS Capital Investment Limited Mauritius - WNS Customer Solutions (Singapore) Private Limited Singapore -WNS Global Services (Australia) Pty Ltd Australia - WNS New Zealand Limited (7) New Zealand -Business Applications Associates Beijing Ltd China WNS Global Services Private Limited (8) India - WNS Global Services (UK) Limited (2) United Kingdom - WNS Global Services SA (Pty) Limited South Africa - WNS B-BBEE (3) South Africa - Ucademy (Pty) Limited (4) South Africa - MTS HealthHelp Inc. (9) Delaware, USA - HealthHelp Holdings LLC (9) Delaware, USA - HealthHelp LLC (9) Delaware, USA - Value Edge Inc. (10) Delaware, USA - Value Edge AG. (10) Switzerland - Value Edge GmbH (10) Germany WNS Global Services (Private) Limited Sri Lanka WNS Global Services (Dalian) Co. Ltd. China Notes: (1) On January 20, 2017, the Company acquired all outstanding equity shares of Denali Sourcing Services Inc. (2) WNS Global Services (UK) is jointly held by WNS Global Services Private Limited and WNS Holdings Limited. The percentage of holding of WNS Global Services Private Limited is 50.7% and of WNS Holdings Limited is 49.3%. (3) The WNS B-BBEE (4) Ucademy (Pty) Limited has been incorporated as a subsidiary of WNS Global Services SA (Pty) Limited with effect from June 20, 2016. (5) WNS Assistance (Legal) Limited, a wholly owned subsidiary of WNS Assistance Limited, was incorporated on April 20, 2016. (6) WNS Legal Assistance LLP is a limited liability partnership, organized under the laws of England and Wales in November 2014. WNS Legal Assistance LLP provides legal services in relation to personal injury claims within the Auto Claims BPM (as defined in Note 26) segment in the UK. During the year ended March 31, 2018, the Company acquired 20% of the equity capital of WNS Legal Assistance LLP from Prettys Solicitors (the non-controlling (7) WNS New Zealand Limited, a wholly owned subsidiary of WNS Global Services (Australia) Pty Ltd, was incorporated on June 13, 2017. (8) WNS Global Services Private Limited is held jointly by WNS (Mauritius) Limited and WNS Customer Solutions (Singapore) Private Limited. The percentage of holding of WNS (Mauritius) Limited is 80% and of WNS Customer Solutions (Singapore) Private Limited is 20%. (9) On March 15, 2017, the Company acquired all ownership interests of MTS HealthHelp Inc. and its subsidiaries, which existed on that date. HealthHelp Holdings LLC is 63.7% owned by MTS HealthHelp Inc. and 36.3% owned by WNS North America Inc. (10) On June 14, 2016, the Company acquired all outstanding equity shares of Value Edge Research Services Private Limited. As part of the acquisition, the Company also acquired the three subsidiaries of Value Edge Research Services Private Limited, which existed on that date. Value Edge Research Services Private Limited was merged with and into WNS Global Services Private Limited pursuant to Scheme of Amalgamation approved by the National Company Law Tribunal on July 27, 2017.
Key Management Personnel Compensation	Year ended March 31, Nature of transaction with related parties 2018 2017 2016 Key management personnel* Remuneration and short-term benefits 6,614 4,592 4,671 Defined contribution plan 94 89 84 Other benefits 17 15 14 Share-based compensation expense 17,677 13,347 8,674 * Defined benefit plan is not disclosed as these are determined for the Company as a whole.

Operating segments (Tables)

Operating segments (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Segment Results for Operating Segments	The segment results for the year ended March 31, 2018 are as follows: Year ended March 31, 2018 WNS Global BPM WNS Auto Claims BPM Inter segments* Total Revenue from external customers $ 722,542 $ 35,414 $ — $ 757,956 Segment revenue $ 722,600 $ 35,414 $ (58 ) $ 757,956 Payments to repair centers — 16,970 — 16,970 Revenue less repair payments (non-GAAP) 722,600 18,444 (58 ) 740,986 Depreciation 19,682 272 — 19,954 Other costs 561,870 18,249 (58 ) 580,061 Segment operating profit 141,048 (77 ) — 140,971 Other income, net (9,757 ) (1,473 ) — (11,230 ) Finance expense 4,065 199 — 4,264 Segment profit before income taxes 146,740 1,197 — 147,937 Provision for income taxes 15,319 112 — 15,431 Segment profit 131,421 1,085 — 132,506 Amortization of intangible assets 15,505 Share based compensation expense 30,565 Profit $ 86,436 Addition to non-current $ 32,337 $ 201 $ — $ 32,538 Total assets, net of elimination 633,186 126,377 — 759,563 Total liabilities, net of elimination $ 181,627 $ 82,980 $ — $ 264,607 * Transactions between inter segments represent invoices issued by WNS Global BPM to WNS Auto Claims BPM for business process management services rendered by the former to the latter. The segment results for the year ended March 31, 2017 are as follows: Year ended March 31, 2017 WNS Global BPM WNS Auto Claims BPM Inter segments* Total Revenue from external customers $ 557,904 $ 44,642 $ — $ 602,546 Segment revenue $ 557,983 $ 44,642 $ (79 ) $ 602,546 Payments to repair centers 24,102 — 24,102 Revenue less repair payments (non-GAAP) 557,983 20,540 (79 ) 578,444 Depreciation 16,598 305 — 16,903 Other costs 429,074 20,147 (79 ) 449,142 Impairment of goodwill (Refer note 9) — 21,673 — 21,673 Segment operating profit/(loss) 112,311 (21,585 ) — 90,726 Other income, net (7,785 ) (904 ) — (8,689 ) Finance expense 547 — — 547 Segment profit/(loss) before income taxes 119,549 (20,681 ) — 98,868 Provision for income taxes 17,441 89 — 17,530 Segment profit/(loss) 102,108 (20,770 ) — 81,338 Amortization of intangible assets 20,539 Share-based compensation expense 23,036 Profit/(loss) $ 37,763 Addition to non-current $ 111,280 $ 453 $ — $ 111,733 Total assets, net of elimination 590,974 113,149 — 704,123 Total liabilities, net of elimination $ 214,155 $ 74,902 $ — $ 289,057 * Transactions between inter segments represent invoices raised by WNS Global BPM on WNS Auto Claims BPM for business process outsourcing services rendered by the former to latter. The segment results for the year ended March 31, 2016 are as follows: Year ended March 31, 2016 WNS Global BPM WNS Auto Claims BPM Inter segments* Total Revenue from external customers $ 508,864 $ 53,315 $ — $ 562,179 Segment revenue $ 509,268 $ 53,315 $ (404 ) $ 562,179 Payments to repair centers — 31,170 — 31,170 Revenue less repair payments (non-GAAP) 509,268 22,145 (404 ) 531,009 Depreciation 15,090 345 — 15,435 Other costs 377,051 22,966 (404 ) 399,613 Segment operating profit/(loss) 117,127 (1,166 ) — 115,961 Other income, net (7,461 ) (1,033 ) — (8,494 ) Finance expense 278 — — 278 Segment profit/(loss) before income taxes 124,310 (133 ) — 124,177 Provision for income taxes 20,905 275 — 21,180 Segment profit/(loss) 103,405 (408 ) — 102,997 Amortization of intangible assets 25,198 Share-based compensation expense 17,919 Profit/(loss) $ 59,880 Addition to non-current $ 30,757 $ 1,101 $ — $ 31,858 Total assets, net of elimination 373,195 152,256 — 525,451 Total liabilities, net of elimination $ 36,660 $ 80,602 $ — $ 117,262 * Transactions between inter segments represent invoices raised by WNS Global BPM on WNS Auto Claims BPM for business process outsourcing services rendered by the former to latter.
External Revenue and Non-current Assets (Excluding Goodwill and Intangible Assets) by Geographic Area	Revenues from the geographic segments based on domicile of the customer. The Company’s external revenue by geographic area is as follows: Year ended March 31, 2018 2017 2016 Jersey, Channel Islands $ — $ — $ — US 308,436 196,193 155,345 UK 258,863 248,588 264,889 Australia 66,626 49,053 40,308 Europe (excluding UK) 47,169 37,494 34,732 South Africa 42,841 42,717 30,086 Rest of the world 34,021 28,501 36,819 Total $ 757,956 $ 602,546 $ 562,179 The Company’s non-current As at March 31, 2018 2017 Jersey, Channel Islands $ — $ — UK 756 1,228 North America 5,112 6,493 India 26,167 21,944 South Africa 10,529 11,449 Philippines 14,050 10,583 Rest of the world 3,992 3,099 Total $ 60,606 $ 54,796

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Future Minimum Lease Payments under Non-cancelable Operating Leases	The details of future minimum lease payments under non-cancelable Operating lease Less than 1 year $ 27,572 1-3 47,115 3-5 29,783 More than 5 years 27,437 Total minimum lease payments $ 131,907

Additional capital disclosures

Additional capital disclosures (Tables)	12 Months Ended
	Mar. 31, 2018
Text block1 [abstract]
Summary of Capital Structure	The capital structure as at March 31, 2018 and 2017 was as follows: As at March 31, 2018 2017 % Change Total equity attributable to the equity shareholders of the Company $ 494,956 $ 415,066 19 % As percentage of total capital 85 % 78 % Long term debt (1) 89,900 118,000 (24 )% Total debt $ 89,900 $ 118,000 (24 )% As percentage of total capital 15 % 22 % Total capital (debt and equity) $ 584,856 $ 533,066 10 % Note: (1) Before netting off debt issuance cost of $769 and $1,257 as at March 31, 2018 and March 31, 2017, respectively.

Summary of Significant Accoun63

Summary of Significant Accounting Policies - Estimated Useful Lives of Property and Equipment (Detail)	12 Months Ended
	Mar. 31, 2018
Buildings [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	20 years
Computers and software [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	3 years
Computers and software [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	4 years
Furniture, fixtures and office equipment [member] | Bottom of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	2 years
Furniture, fixtures and office equipment [member] | Top of range [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	5 years
Vehicles [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	3 years
Leasehold improvements [member]
Disclosure of detailed information about property, plant and equipment [line items]
Estimated useful lives of property and equipment	Lesser of estimated useful life or lease term

Summary of Significant Accoun64

Summary of Significant Accounting Policies - Estimated Useful Life of Intangible Assets (Detail)	12 Months Ended
	Mar. 31, 2018
Customer contracts [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	48 months
Customer relationships [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	217 months
Covenant not-to-compete [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	48 months
Trade names [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	34 months
Technology [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	94 months
Intellectual property and other rights [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	24 months
Software [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	55 months
Service mark [member]
Disclosure of detailed information about intangible assets [line items]
Weighted average amortization period of definite lived intangible assets	Indefinite useful life

Summary of Significant Accoun65

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	12 Months Ended
	Mar. 31, 2018USD ($)
Disclosure of defined benefit plans [abstract]
Approximate maximum amount per employee available for lump-sum payment to eligible employees in India	$ 31

Business Combinations - Additio

Business Combinations - Additional Information (Detail) R in Thousands, $ in Thousands	Jan. 01, 2018USD ($)	Mar. 15, 2017USD ($)	Jan. 20, 2017USD ($)	Jun. 14, 2016USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2018USD ($)	Mar. 31, 2017USD ($)	May 01, 2015USD ($)	May 01, 2015ZAR (R)
Disclosure of detailed information about business combination [line items]
Payment of contingent consideration						$ 5,465
Release of restricted cash, held in escrow						1,535
Denali Sourcing Services Inc. [member]
Disclosure of detailed information about business combination [line items]
Percentage of ownership interests acquired			100.00%
Purchase consideration			$ 38,668
Working capital adjustments						(968)
Contingent consideration			$ 6,277
Contingent consideration payable period			Three years
Discount rate used for estimating fair value of contingent consideration liability			2.5 percent
Acquisition related costs							$ 502
Payment of contingent consideration	$ 2,351
Deferred consideration			$ 522				522
Payment of deferred consideration						522
Denali Sourcing Services Inc. [member] | Bottom of range [member]
Disclosure of detailed information about business combination [line items]
Potential undiscounted amount of all future payments that could be required to make under the contingent consideration arrangement			0
Denali Sourcing Services Inc. [member] | Top of range [member]
Disclosure of detailed information about business combination [line items]
Potential undiscounted amount of all future payments that could be required to make under the contingent consideration arrangement			$ 6,578
Value Edge Research Services Private Limited [member]
Disclosure of detailed information about business combination [line items]
Percentage of ownership interests acquired				100.00%
Purchase consideration				$ 18,265
Working capital adjustments				765
Contingent consideration				$ 5,112
Contingent consideration payable period				Three years
Acquisition related costs							24
Release of restricted cash, held in escrow						1,535
Telkom SA SOC Limited [member]
Disclosure of detailed information about business combination [line items]
Purchase consideration								$ 3,331
Purchase consideration in cash based on exchange rate on September 30, 2015								$ 2,572	R 35,639
MTS HealthHelp Inc. [member]
Disclosure of detailed information about business combination [line items]
Percentage of ownership interests acquired		100.00%
Purchase consideration		$ 68,910
Working capital adjustments		573
Contingent consideration		$ 8,545
Contingent consideration payable period		Two years
Discount rate used for estimating fair value of contingent consideration liability		2.5 percent
Acquisition related costs							$ 1,809
Payment for working capital adjustments						$ 573
Reversal of contingent consideration in relation to acquisition					$ 1,324
Payment of contingent consideration					$ 3,114
Goodwill expected to be deductible for tax purposes		$ 14,876
MTS HealthHelp Inc. [member] | Bottom of range [member]
Disclosure of detailed information about business combination [line items]
Potential undiscounted amount of all future payments that could be required to make under the contingent consideration arrangement		0
MTS HealthHelp Inc. [member] | Top of range [member]
Disclosure of detailed information about business combination [line items]
Potential undiscounted amount of all future payments that could be required to make under the contingent consideration arrangement		$ 8,876

Business Combinations - Purchas

Business Combinations - Purchase Price Allocation to Assets Acquired and Liabilities Assumed of MTS HealthHelp Inc. (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 15, 2017
Disclosure of detailed information about business combination [line items]
Goodwill on acquisition	$ 135,186	$ 134,008
MTS HealthHelp Inc. [member]
Disclosure of detailed information about business combination [line items]
Cash			$ 3,119
Trade receivables			4,910
Unbilled revenue			2,016
Prepayments and other current assets			1,060
Property and equipment			4,612
Non-current assets			161
Term loan			(29,249)
Current liabilities			(2,555)
Non-current liabilities			(1,423)
Deferred tax liability			(18,163)
Net assets acquired			29,828
Less: Purchase consideration			68,910
Goodwill on acquisition			39,082
MTS HealthHelp Inc. [member] | Software [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			1,274
MTS HealthHelp Inc. [member] | Customer contracts [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			4,537
MTS HealthHelp Inc. [member] | Customer relationships [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			49,584
MTS HealthHelp Inc. [member] | Service mark [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			400
MTS HealthHelp Inc. [member] | Covenant not-to-compete [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			4,693
MTS HealthHelp Inc. [member] | Technology [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			$ 4,852

Business Combinations - Purch68

Business Combinations - Purchase Price Allocation to Assets Acquired and Liabilities Assumed of Denali Sourcing Services Inc. (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Jan. 20, 2017
Disclosure of detailed information about business combination [line items]
Goodwill on acquisition	$ 135,186	$ 134,008
Denali Sourcing Services Inc. [member]
Disclosure of detailed information about business combination [line items]
Cash			$ 1,204
Trade receivables			2,799
Unbilled revenue			1,258
Prepayments and other current assets			95
Property and equipment			53
Deferred tax asset			18
Non-current assets			27
Current liabilities			(3,781)
Short-term line of credit		$ (475)	(475)
Non-current liabilities			(343)
Deferred tax liability			(5,020)
Net assets acquired			9,126
Less: Purchase consideration			38,668
Goodwill on acquisition			29,542
Denali Sourcing Services Inc. [member] | Software [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			3
Denali Sourcing Services Inc. [member] | Customer contracts [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			3,025
Denali Sourcing Services Inc. [member] | Customer relationships [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			8,000
Denali Sourcing Services Inc. [member] | Trade names [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			545
Denali Sourcing Services Inc. [member] | Covenant not-to-compete [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			$ 1,718

Business Combinations - Purch69

Business Combinations - Purchase Price Allocation to Assets Acquired and Liabilities Assumed of Value Edge Research Services Private Limited (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Jun. 14, 2016
Disclosure of detailed information about business combination [line items]
Goodwill on acquisition	$ 135,186	$ 134,008
Value Edge Research Services Private Limited [member]
Disclosure of detailed information about business combination [line items]
Cash			$ 432
Trade receivables			370
Unbilled revenue			706
Investments			87
Prepayments and other current assets			99
Property and equipment			78
Deferred tax asset			49
Non-current assets			74
Current liabilities			(1,236)
Non-current liabilities			(126)
Deferred tax liability			(2,281)
Net assets acquired			4,854
Less: Purchase consideration			18,265
Goodwill on acquisition			13,411
Value Edge Research Services Private Limited [member] | Software [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			10
Value Edge Research Services Private Limited [member] | Customer contracts [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			701
Value Edge Research Services Private Limited [member] | Customer relationships [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			1,894
Value Edge Research Services Private Limited [member] | Trade names [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			104
Value Edge Research Services Private Limited [member] | Covenant not-to-compete [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			2,655
Value Edge Research Services Private Limited [member] | Technology [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			$ 1,238

Business Combinations - Purch70

Business Combinations - Purchase Price Allocation to Assets Acquired and Liabilities Assumed of Telkom SA SOC LIMITED (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	May 01, 2015
Disclosure of detailed information about business combination [line items]
Goodwill on acquisition	$ 135,186	$ 134,008
Telkom SA SOC Limited [member]
Disclosure of detailed information about business combination [line items]
Cash			$ 411
Accrued leave liability			(411)
Deferred tax liabilities			(837)
Net assets acquired			2,153
Less: Purchase consideration			3,331
Goodwill on acquisition			1,178
Telkom SA SOC Limited [member] | Customer contracts [member]
Disclosure of detailed information about business combination [line items]
Intangible assets			$ 2,990

Cash and Cash Equivalents - Sum

Cash and Cash Equivalents - Summary of Cash and Cash Equivalents (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Cash and cash equivalents [abstract]
Cash and bank balances	$ 47,738	$ 46,110
Short term deposits with banks	52,091	23,693
Total	$ 99,829	$ 69,803	$ 41,854	$ 32,448

Investments - Summary of Invest

Investments - Summary of Investments (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Categories of financial assets [abstract]
Investments in marketable securities and mutual funds	$ 99,954	$ 87,652
Investments in FMPs		96
Investment in fixed deposits	21,548	24,673
Current investments	120,960	111,992
Non-current investment	542	429
Total	$ 121,502	$ 112,421

Trade Receivables, Net - Summar

Trade Receivables, Net - Summary of Trade Receivables (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Trade and other receivables [abstract]
Trade receivables	$ 71,952	$ 62,136
Less Allowances for doubtful trade receivable	(564)	(1,713)
Total	$ 71,388	$ 60,423

Trade Receivables, Net - Moveme

Trade Receivables, Net - Movement in Allowances for Doubtful Trade Receivable (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of financial assets [line items]
Balance at the beginning of the year	$ 1,713
Balance at the end of the year	564	$ 1,713
Allowances for doubtful trade receivable [member]
Disclosure of financial assets [line items]
Balance at the beginning of the year	1,713	4,446	$ 5,336
Charged to operations	2,115	777	1,010
Write-offs, net of collections	(1,136)	(2,571)	(936)
Reversals	(2,321)	(664)	(904)
Translation adjustment	193	(275)	(60)
Balance at the end of the year	$ 564	$ 1,713	$ 4,446

Prepayments and Other Assets -

Prepayments and Other Assets - Summary of Prepayment and Other Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current:
Service tax and other tax receivables	$ 6,569	$ 8,029
Deferred transition cost	571	423
Employee receivables	1,099	1,215
Advances to suppliers	2,877	2,087
Prepaid expenses	7,994	8,819
Restricted cash, held in escrow (Refer Note 4(c))	1,535	1,611
Other assets	4,202	5,201
Total	24,847	27,385
Non-current:
Deposits	8,708	7,569
Income tax assets	12,595	10,202
Service tax and other tax receivables	11,410	6,236
Deferred transition cost	2,467	365
Restricted cash, held in escrow (Refer Note 4(c))	1,535	3,222
Others assets	5,673	4,350
Total	$ 42,388	$ 31,944

Goodwill - Summary of the Carry

Goodwill - Summary of the Carrying Value of Goodwill (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of reconciliation of changes in goodwill [line items]
Goodwill	$ 135,186	$ 134,008
Gross carrying value [member]
Disclosure of reconciliation of changes in goodwill [line items]
Goodwill	159,500	155,681	$ 76,242
Accumulated impairment [member]
Disclosure of reconciliation of changes in goodwill [line items]
Goodwill	$ (24,314)	$ (21,673)

Goodwill - Summary of Movement

Goodwill - Summary of Movement in Goodwill by Reportable Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	$ 134,008
Impairment of goodwill recognized during the year	0	$ 21,673
Ending balance	135,186	134,008
Accumulated impairment [member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	(21,673)
Impairment of goodwill recognized during the year		21,673
Foreign currency translation	(2,641)
Ending balance	(24,314)	(21,673)
Accumulated impairment [member] | WNS Auto Claims BPM [member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	(21,673)
Impairment of goodwill recognized during the year		21,673
Foreign currency translation	(2,641)
Ending balance	(24,314)	(21,673)
Gross carrying value [member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	155,681	76,242
Goodwill arising on acquisitions	(92)	82,127
Foreign currency translation	3,911	(2,688)
Ending balance	159,500	155,681
Gross carrying value [member] | WNS global BPM [member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	129,878	46,503
Goodwill arising on acquisitions	(92)	82,127
Foreign currency translation	767	1,248
Ending balance	130,553	129,878
Gross carrying value [member] | WNS Auto Claims BPM [member]
Disclosure of reconciliation of changes in goodwill [line items]
Beginning balance	25,803	29,739
Foreign currency translation	3,144	(3,936)
Ending balance	$ 28,947	$ 25,803

Goodwill - Carrying Value of Go

Goodwill - Carrying Value of Goodwill Allocated to Cash Generating Units (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of information for cash-generating units [line items]
Goodwill	$ 135,186	$ 134,008
WNS global BPM [member]
Disclosure of information for cash-generating units [line items]
Goodwill	3,815	3,815
South Africa [member]
Disclosure of information for cash-generating units [line items]
Goodwill	5,581	4,963
Research & analytics [member]
Disclosure of information for cash-generating units [line items]
Goodwill	48,901	49,146
Technology services [member]
Disclosure of information for cash-generating units [line items]
Goodwill	3,632	3,238
WNS Auto Claims BPM [member]
Disclosure of information for cash-generating units [line items]
Goodwill	4,633	4,130
Finance and accounting [member]
Disclosure of information for cash-generating units [line items]
Goodwill	29,542	29,874
Healthcare [member]
Disclosure of information for cash-generating units [line items]
Goodwill	$ 39,082	$ 38,842

Goodwill - Additional Informati

Goodwill - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure of reconciliation of changes in goodwill [line items]
Estimated cash flows period	P5Y
Impairment charge	$ 0	$ (21,673)
Goodwill	$ 135,186	134,008
WNS Auto Claims BPM [member]
Disclosure of reconciliation of changes in goodwill [line items]
Impairment charge		$ 21,673
Discount rate	14.00%	13.00%
Growth rate	2.00%
Recoverable amount of cash generating units		$ 37,836
Goodwill	$ 4,633	4,130
Disposal cost		$ 656
WNS Auto Claims BPM [member] | Annual Growth Rate [member]
Disclosure of reconciliation of changes in goodwill [line items]
Growth rate		2.50%
WNS Auto Claims BPM [member] | Perpetual Growth Rate [member]
Disclosure of reconciliation of changes in goodwill [line items]
Growth rate		2.00%

Goodwill - Key Assumptions Used

Goodwill - Key Assumptions Used in Performing Impairment Test, by each CGU (Detail)	Mar. 31, 2018	Mar. 31, 2017
WNS global BPM [member]
Disclosure of information for cash-generating units [line items]
Discount rate	16.00%
Perpetual growth rate	3.00%
South Africa [member]
Disclosure of information for cash-generating units [line items]
Discount rate	17.10%
Perpetual growth rate	3.00%
Finance and accounting [member]
Disclosure of information for cash-generating units [line items]
Discount rate	15.10%
Perpetual growth rate	2.00%
Research & analytics [member]
Disclosure of information for cash-generating units [line items]
Discount rate	16.00%
Perpetual growth rate	3.00%
Healthcare [member]
Disclosure of information for cash-generating units [line items]
Discount rate	13.00%
Perpetual growth rate	2.50%
Technology services [member]
Disclosure of information for cash-generating units [line items]
Discount rate	14.00%
Perpetual growth rate	3.00%
WNS Auto Claims BPM [member]
Disclosure of information for cash-generating units [line items]
Discount rate	14.00%	13.00%
Perpetual growth rate	2.00%

Intangible Assets - Change in C

Intangible Assets - Change in Carrying Value of Intangible Assets (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of detailed information about intangible assets [line items]
Beginning balance	$ 96,624
Amortization	(15,505)	$ (20,539)	$ (25,198)
Ending balance	89,652	96,624
Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	336,840	246,304
Additions	7,619	4,611
On acquisition		85,233
Translation adjustments	2,401	692
Ending balance	346,860	336,840	246,304
Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	240,216	219,187
Amortization	15,505	20,539
Translation adjustments	1,487	490
Ending balance	257,208	240,216	219,187
Customer contracts [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	9,025
Ending balance	6,455	9,025
Customer contracts [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	167,001	156,786
On acquisition		8,263
Translation adjustments	93	1,952
Ending balance	167,094	167,001	156,786
Customer contracts [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	157,976	145,483
Amortization	2,725	10,653
Translation adjustments	(62)	1,840
Ending balance	160,639	157,976	145,483
Customer relationships [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	59,747
Ending balance	56,114	59,747
Customer relationships [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	121,922	63,147
On acquisition		59,478
Translation adjustments	940	(703)
Ending balance	122,862	121,922	63,147
Customer relationships [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	62,175	58,992
Amortization	3,700	4,016
Translation adjustments	873	(833)
Ending balance	66,748	62,175	58,992
Intellectual property rights [member]
Disclosure of detailed information about intangible assets [line items]
Ending balance	176
Intellectual property rights [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	3,861	4,450
Additions	250
Translation adjustments	470	(589)
Ending balance	4,581	3,861	4,450
Intellectual property rights [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	3,861	4,450
Amortization	74
Translation adjustments	470	(589)
Ending balance	4,405	3,861	4,450
Trade names [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	573
Ending balance	338	573
Trade names [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	653
On acquisition		649
Translation adjustments		4
Ending balance	653	653
Trade names [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	80
Amortization	236	78
Translation adjustments	(1)	2
Ending balance	315	80
Technology [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	5,959
Ending balance	5,167	5,959
Technology [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	6,131
On acquisition		6,090
Translation adjustments	(6)	41
Ending balance	6,125	6,131
Technology [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	172
Amortization	790	167
Translation adjustments	(4)	5
Ending balance	958	172
Leasehold benefits [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	1,835	1,835
Ending balance	1,835	1,835	1,835
Leasehold benefits [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	1,835	1,835
Ending balance	1,835	1,835	1,835
Covenant not-to-compete [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	8,487
Ending balance	6,175	8,487
Covenant not-to-compete [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	9,451	326
On acquisition		9,066
Translation adjustments	10	59
Ending balance	9,461	9,451	326
Covenant not-to-compete [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	964	326
Amortization	2,310	650
Translation adjustments	12	(12)
Ending balance	3,286	964	326
Service mark [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	400
Ending balance	400	400
Service mark [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	400
On acquisition		400
Ending balance	400	400
Software [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	12,433
Ending balance	14,827	12,433
Software [member] | Gross carrying value [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	25,586	19,760
Additions	7,369	4,611
On acquisition		1,287
Translation adjustments	894	(72)
Ending balance	33,849	25,586	19,760
Software [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about intangible assets [line items]
Beginning balance	13,153	8,101
Amortization	5,670	4,975
Translation adjustments	199	77
Ending balance	$ 19,022	$ 13,153	$ 8,101

Intangible Assets - Estimated R

Intangible Assets - Estimated Remaining Weighted Average Amortization Periods for Definite Lived Intangible Assets (Detail) - Remaining weighted average [member]	12 Months Ended
	Mar. 31, 2018
Customer contracts [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	29 months
Customer relationships [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	196 months
Covenant not-to-compete [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	33 months
Trade names [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	21 months
Technology [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	80 months
Intellectual property and other rights [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	17 months
Software [member]
Disclosure of detailed information about intangible assets [line items]
Estimated remaining weighted average amortization periods	24 months

Intangible Assets - Estimated A

Intangible Assets - Estimated Annual Amortization Expense (Detail) $ in Thousands	12 Months Ended
	Mar. 31, 2018USD ($)
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	$ 89,252
2019 [member]
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	15,279
2020 [member]
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	14,204
2021 [member]
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	9,700
2022 [member]
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	6,095
2023 [member]
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	5,047
More than 5 years [member]
Disclosure of intangible assets with indefinite useful life [line items]
Estimated annual amortization expense	$ 38,927

Property and Equipment - Change

Property and Equipment - Changes in Carrying Value of Property and Equipment (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	$ 54,796
Capital work-in-progress	2,366	$ 1,282
Ending balance	60,606	54,796
Gross carrying value [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	210,573	193,261
Additions	23,835	20,106
On acquisition		4,743
Disposals/retirements	(7,400)	(6,782)
Translation adjustments	3,507	(755)
Ending balance	230,515	210,573
Accumulated depreciation and amortization [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	157,059	147,025
Depreciation	19,954	16,903
Disposals/retirements	(7,357)	(5,942)
Translation adjustments	2,619	(927)
Ending balance	172,275	157,059
Buildings [member] | Gross carrying value [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	10,246	10,150
Translation adjustments	(23)	96
Ending balance	10,223	10,246
Buildings [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	4,208	3,661
Depreciation	514	505
Translation adjustments	(12)	42
Ending balance	4,710	4,208
Computers and software [member] | Gross carrying value [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	69,871	69,203
Additions	4,597	4,411
On acquisition		1,014
Disposals/retirements	(3,350)	(3,407)
Translation adjustments	1,965	(1,350)
Ending balance	73,083	69,871
Computers and software [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	59,811	58,768
Depreciation	6,442	5,742
Disposals/retirements	(3,345)	(3,327)
Translation adjustments	1,822	(1,372)
Ending balance	64,730	59,811
Furniture, fixtures and office equipment [member] | Gross carrying value [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	68,877	60,860
Additions	9,389	7,455
On acquisition		1,895
Disposals/retirements	(1,718)	(1,619)
Translation adjustments	839	286
Ending balance	77,387	68,877
Furniture, fixtures and office equipment [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	51,431	47,375
Depreciation	6,623	5,126
Disposals/retirements	(1,674)	(1,241)
Translation adjustments	512	171
Ending balance	56,892	51,431
Vehicles [member] | Gross carrying value [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	587	459
Additions	93	135
On acquisition		14
Disposals/retirements	(29)	(33)
Translation adjustments	5	12
Ending balance	656	587
Vehicles [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	429	347
Depreciation	97	92
Disposals/retirements	(30)	(20)
Translation adjustments	1	10
Ending balance	497	429
Leasehold improvements [member] | Gross carrying value [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	60,992	52,589
Additions	9,756	8,105
On acquisition		1,820
Disposals/retirements	(2,303)	(1,723)
Translation adjustments	721	201
Ending balance	69,166	60,992
Leasehold improvements [member] | Accumulated depreciation and amortization [member]
Disclosure of detailed information about property, plant and equipment [line items]
Beginning balance	41,180	36,874
Depreciation	6,278	5,438
Disposals/retirements	(2,308)	(1,354)
Translation adjustments	296	222
Ending balance	$ 45,446	$ 41,180

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about property, plant and equipment [abstract]
Property and equipment pledged as collateral against borrowings	$ 107	$ 170

Loans and Borrowings - Summary

Loans and Borrowings - Summary of Long-term Loans and Borrowings (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about borrowings [line items]
Total long term debt		$ 89,900	$ 118,000
Unamortised debt issuance cost		769	1,257
Total long term debt		89,131	116,743
Current portion of long term debt		27,740	27,613
Long term debt		$ 61,391	89,130
Long term loan to finance acquisition of denali [member]
Disclosure of detailed information about borrowings [line items]
Interest rate basis	3M USD Libor	3M USD Libor
Adjustment to interest rate basis	1.27%	1.27%
Final maturity (fiscal year)		2,020
Total long term debt		$ 22,700	34,000
Long term loan to finance acquisition of health help [member]
Disclosure of detailed information about borrowings [line items]
Interest rate basis		3M USD Libor
Adjustment to interest rate basis		0.95%
Final maturity (fiscal year)		2,022
Total long term debt		$ 67,200	$ 84,000

Loans and Borrowings - Addition

Loans and Borrowings - Additional Information (Detail) $ in Thousands	Mar. 14, 2018USD ($)	Jan. 22, 2018USD ($)	Sep. 14, 2017USD ($)	Jul. 20, 2017USD ($)	Jan. 31, 2017USD ($)Installments	Mar. 31, 2018USD ($)Installments	Mar. 31, 2017USD ($)
Disclosure of detailed information about borrowings [line items]
Pledged trade receivables, other financial assets, property and equipment, intangible and other assets						$ 113,174	$ 88,730
Line of credit						78,290
Line of credit [member] | UK [member]
Disclosure of detailed information about borrowings [line items]
Line of credit						13,840
Line of credit [member] | South Africa [member]
Disclosure of detailed information about borrowings [line items]
Line of credit						1,732
Line of credit [member] | WNS Global Services Private Limited [member]
Disclosure of detailed information about borrowings [line items]
Line of credit						$ 62,718
Long term loan to finance acquisition of denali [member]
Disclosure of detailed information about borrowings [line items]
Term loan facility tenure					3 years
Term loan facility amount					$ 34,000
Interest rate basis					3M USD Libor	3M USD Libor
Adjustment to interest rate basis					1.27%	1.27%
Repayment installment term | Installments					6
First five repayment installments amount					$ 5,650
Sixth and final repayment installment					$ 5,750
Repayment of installment		$ 5,650		$ 5,650
Long term loan to finance acquisition of denali [member] | Fixed interest rate [member]
Disclosure of detailed information about borrowings [line items]
Fixed rate					1.561%
Long term loan to finance acquisition of health help [member]
Disclosure of detailed information about borrowings [line items]
Term loan facility tenure						5 years
Term loan facility amount						$ 84,000
Interest rate basis						3M USD Libor
Adjustment to interest rate basis						0.95%
Repayment installment term | Installments						10
Repayment of installment	$ 8,400		$ 8,400
Repayment installment amount						$ 8,400
Long term loan to finance acquisition of health help [member] | Fixed interest rate [member]
Disclosure of detailed information about borrowings [line items]
Fixed rate						1.9635%

Financial Instruments - Carryin

Financial Instruments - Carrying Value and Fair Value of Financial Instruments by Class (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	$ 99,829	$ 69,803	$ 41,854	$ 32,448
Investment in fixed deposits	21,548	24,673
Investments in marketable securities and mutual funds	99,954	87,652
Investment in FMPs		96
Trade receivables	71,388	60,423
Unbilled revenue	61,721	48,915
Funds held for clients	10,066	9,135
Prepayments and other assets	4,410	4,262
Other non-current assets	10,243	10,791
Derivative assets	14,983	41,982
Total carrying value	394,142	357,732
Trade payables	19,703	14,239
Long term debt (includes current portion)	89,900	118,000
Other employee obligations	59,346	46,701
Provision and accrued expenses	28,826	27,217
Other liabilities	13,835	20,764
Derivative liabilities	8,755	4,783
Total carrying value	220,365	231,704
Financial liabilities at FVTPL [member]
Disclosure of detailed information about financial instruments [line items]
Other liabilities	11,388	19,678
Derivative liabilities	946	26
Total carrying value	12,334	19,704
Derivative designated as cash flow hedges (carried at fair value) [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities	7,809	4,757
Total carrying value	7,809	4,757
Financial liabilities at amortized cost [member]
Disclosure of detailed information about financial instruments [line items]
Trade payables	19,703	14,239
Long term debt (includes current portion)	89,900	118,000
Other employee obligations	59,346	46,701
Provision and accrued expenses	28,826	27,217
Other liabilities	2,447	1,086
Total carrying value	200,222	207,243
Financial liabilities at fair value, class [member]
Disclosure of detailed information about financial instruments [line items]
Trade payables	19,703	14,239
Long term debt (includes current portion)	89,900	118,000
Other employee obligations	59,346	46,701
Provision and accrued expenses	28,826	27,217
Other liabilities	13,835	20,764
Derivative liabilities	8,755	4,783
Total carrying value	220,365	231,704
Loans and receivables [member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	99,829	69,803
Investment in fixed deposits	21,548	24,673
Trade receivables	71,388	60,423
Unbilled revenue	61,721	48,915
Funds held for clients	10,066	9,135
Prepayments and other assets	4,410	4,262
Other non-current assets	10,243	10,791
Total carrying value	279,205	228,002
Financial assets at FVTPL [member]
Disclosure of detailed information about financial instruments [line items]
Investment in FMPs		96
Derivative assets	2,212	5,041
Total carrying value	2,212	5,137
Derivative designated as cash flow hedges (carried at fair value) [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	12,771	36,941
Total carrying value	12,771	36,941
Available for sale [member]
Disclosure of detailed information about financial instruments [line items]
Investments in marketable securities and mutual funds	99,954	87,652
Total carrying value	99,954	87,652
Financial assets at fair value, class [member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	99,829	69,803
Investment in fixed deposits	21,548	24,673
Investments in marketable securities and mutual funds	99,954	87,652
Investment in FMPs		96
Trade receivables	71,388	60,423
Unbilled revenue	61,721	48,915
Funds held for clients	10,066	9,135
Prepayments and other assets	4,410	4,262
Other non-current assets	10,243	10,791
Derivative assets	14,983	41,982
Total carrying value	$ 394,142	$ 357,732

Financial Instruments - Carry89

Financial Instruments - Carrying Value and Fair Value of Financial Instruments by Class (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about financial instruments [line items]
Prepayments and other assets	$ 24,847	$ 27,385
Other non-current assets	42,388	31,944
Unamortised debt issuance cost	769	1,257
Other employee obligations	64,617	52,933
Other liabilities	15,739	16,015
Non-financial instruments [member]
Disclosure of detailed information about financial instruments [line items]
Prepayments and other assets	20,437	23,123
Other non-current assets	32,145	21,153
Unamortised debt issuance cost	769	1,257
Other employee obligations	14,892	16,912
Other liabilities	$ 13,566	$ 13,720

Financial Instruments - Financi

Financial Instruments - Financial Assets and Liabilities Subject to Offsetting, Enforceable Master Netting Arrangements or Similar Agreements (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of offsetting of financial assets liabilities [Line Items]
Gross amounts of recognized financial assets	$ 14,983	$ 41,982
Gross amounts of recognized financial liabilities offset in the statement of financial position	0	0
Net amounts of financial assets presented in the statement of financial position	14,983	41,982
Related amount not set off in financial instruments, Financial instruments, financial assets	(4,215)	(1,712)
Related amount not set off in financial instruments, Cash collateral received, financial assets	0	0
Net Amount, financial assets	10,768	40,270
Gross amounts of recognized financial liabilities	8,755	4,783
Gross amounts of recognized financial assets offset in the statement of financial position	0	0
Net amounts of financial liabilities presented in the statement of financial position	8,755	4,783
Related amount not set off in financial instruments, Financial instruments, financial liabilities	(4,215)	(1,712)
Related amount not set off in financial instruments, Cash collateral received, financial liabilities	0	0
Net Amount, financial liabilities	4,540	3,071
Derivatives [member]
Disclosure of offsetting of financial assets liabilities [Line Items]
Gross amounts of recognized financial assets	14,983	41,982
Gross amounts of recognized financial liabilities offset in the statement of financial position	0	0
Net amounts of financial assets presented in the statement of financial position	14,983	41,982
Related amount not set off in financial instruments, Financial instruments, financial assets	(4,215)	(1,712)
Related amount not set off in financial instruments, Cash collateral received, financial assets	0	0
Net Amount, financial assets	10,768	40,270
Gross amounts of recognized financial liabilities	8,755	4,783
Gross amounts of recognized financial assets offset in the statement of financial position	0	0
Net amounts of financial liabilities presented in the statement of financial position	8,755	4,783
Related amount not set off in financial instruments, Financial instruments, financial liabilities	(4,215)	(1,712)
Related amount not set off in financial instruments, Cash collateral received, financial liabilities	0	0
Net Amount, financial liabilities	$ 4,540	$ 3,071

Financial Instruments - Assets

Financial Instruments - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about financial instruments [line items]
Derivative assets	$ 14,983	$ 41,982
Investments in marketable securities and mutual funds	99,954	87,652
Total assets	394,142	357,732
Derivative liabilities	8,755	4,783
Total liabilities	220,365	231,704
Investment in FMPs		96
Fair value on recurring basis [member]
Disclosure of detailed information about financial instruments [line items]
Total assets	114,937	129,730
Total liabilities	20,143	24,461
Fair value on recurring basis [member] | Financial assets at FVTPL [member]
Disclosure of detailed information about financial instruments [line items]
Investment in FMPs		96
Fair value on recurring basis [member] | Financial assets at FVTPL [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	2,212	5,041
Fair value on recurring basis [member] | Financial assets at fair value through other comprehensive income [member]
Disclosure of detailed information about financial instruments [line items]
Investments in marketable securities and mutual funds	99,954	87,652
Fair value on recurring basis [member] | Financial assets at fair value through other comprehensive income [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	11,709	36,733
Fair value on recurring basis [member] | Financial assets at fair value through other comprehensive income [member] | Interest rate swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	1,062	208
Fair value on recurring basis [member] | Financial liabilities at FVTPL [member]
Disclosure of detailed information about financial instruments [line items]
Contingent consideration	11,388	19,678
Fair value on recurring basis [member] | Financial liabilities at FVTPL [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities	946	26
Fair value on recurring basis [member] | Financial liabilities at fair value through other comprehensive income [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities	7,809	4,136
Fair value on recurring basis [member] | Financial liabilities at fair value through other comprehensive income [member] | Interest rate swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities		621
Fair value on recurring basis [member] | Level 1 [member]
Disclosure of detailed information about financial instruments [line items]
Total assets	99,412	87,319
Fair value on recurring basis [member] | Level 1 [member] | Financial assets at FVTPL [member]
Disclosure of detailed information about financial instruments [line items]
Investment in FMPs		96
Fair value on recurring basis [member] | Level 1 [member] | Financial assets at fair value through other comprehensive income [member]
Disclosure of detailed information about financial instruments [line items]
Investments in marketable securities and mutual funds	99,412	87,223
Fair value on recurring basis [member] | Level 2 [member]
Disclosure of detailed information about financial instruments [line items]
Total assets	15,525	42,411
Total liabilities	8,755	4,783
Fair value on recurring basis [member] | Level 2 [member] | Financial assets at FVTPL [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	2,212	5,041
Fair value on recurring basis [member] | Level 2 [member] | Financial assets at fair value through other comprehensive income [member]
Disclosure of detailed information about financial instruments [line items]
Investments in marketable securities and mutual funds	542	429
Fair value on recurring basis [member] | Level 2 [member] | Financial assets at fair value through other comprehensive income [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	11,709	36,733
Fair value on recurring basis [member] | Level 2 [member] | Financial assets at fair value through other comprehensive income [member] | Interest rate swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative assets	1,062	208
Fair value on recurring basis [member] | Level 2 [member] | Financial liabilities at FVTPL [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities	946	26
Fair value on recurring basis [member] | Level 2 [member] | Financial liabilities at fair value through other comprehensive income [member] | Foreign exchange contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities	7,809	4,136
Fair value on recurring basis [member] | Level 2 [member] | Financial liabilities at fair value through other comprehensive income [member] | Interest rate swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Derivative liabilities		621
Fair value on recurring basis [member] | Level 3 [member]
Disclosure of detailed information about financial instruments [line items]
Contingent consideration	11,388	19,678
Total liabilities	11,388	19,678
Fair value on recurring basis [member] | Level 3 [member] | Financial liabilities at FVTPL [member]
Disclosure of detailed information about financial instruments [line items]
Contingent consideration	$ 11,388	$ 19,678

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) - USD ($)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of detailed information about financial instruments [line items]
Transfers between Level 1 and Level 2 fair value measurements, financial assets	$ 0	$ 0
Transfers between Level 1 and Level 2 fair value measurements, financial liabilities	0	0
Transfers between Level 2 and Level 1 fair value measurements, financial assets	0	0
Transfers between Level 2 and Level 1 fair value measurements, financial liabilities	0	0
Transfers into Level 3 fair value measurements, financial assets	0	0
Transfers into Level 3 fair value measurements, financial liabilities	0	0
Transfers out of Level 3 fair value measurements, financial assets	0	0
Transfers out of Level 3 fair value measurements, financial liabilities	0	0
Gain (loss) recognized due to discontinuation of cash flow hedge accounting	(20,000)	$ 666,000	$ 125,000
Unused lines of credit	78,290,000
Level 3 [member]
Disclosure of detailed information about financial instruments [line items]
Discount rate used to determine fair value of the contingent consideration liability		2.50%
Level 3 [member] | Non-recurring fair value measurement [member]
Disclosure of detailed information about financial instruments [line items]
Fair value measurement for Auto Claim BPM CGU	38,492,000
Disposal cost	656,000
Interest rate swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Outstanding swap agreement	$ 89,900,000
Currency risk [member]
Disclosure of detailed information about financial instruments [line items]
Rate of appreciation or depreciation of the foreign currencies against the functional currency of the company	5.00%
Effect on statement of profit before tax from operating activities due to appreciation or depreciation of the foreign currencies against the functional currency of the company	$ 3,751,000
Currency risk [member] | United Kingdom Pound Sterling [member]
Disclosure of detailed information about financial instruments [line items]
Rate of appreciation or depreciation of the foreign currencies against the functional currency of the company	10.00%
Effect on statement of profit before tax from operating activities due to appreciation or depreciation of the foreign currencies against the functional currency of the company	$ 24,107,000
Currency risk [member] | Indian Rupees [member]
Disclosure of detailed information about financial instruments [line items]
Rate of appreciation or depreciation of the foreign currencies against the functional currency of the company	10.00%
Effect on statement of profit before tax from operating activities due to appreciation or depreciation of the foreign currencies against the functional currency of the company	$ 27,282,000
Forward and option contracts [member]
Disclosure of detailed information about financial instruments [line items]
Gain (loss) on cash flow hedges, expected to be reclassified from other comprehensive income into profit (loss)	$ 1,015,000
Reclassification period for cash flow hedges	24 months
Interest rate swap contracts [member]
Disclosure of detailed information about financial instruments [line items]
Gain (loss) on cash flow hedges, expected to be reclassified from other comprehensive income into profit (loss)	$ 995,000
Reclassification period for cash flow hedges	48 months

Financial Instruments - Movemen

Financial Instruments - Movement in Contingent Consideration Categorized Under Level 3 Fair Value Measurement (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about financial instruments [line items]
Payouts	$ 5,465
Fair value on recurring basis [member] | Level 3 [member]
Disclosure of detailed information about financial instruments [line items]
Beginning balance	19,678
Additions		$ 19,934
Payouts	(7,000)
Gain recognized in the consolidated statement of income	(1,553)	(279)
Finance expense recognized in the consolidated statement of income	263	23
Ending Balance	$ 11,388	$ 19,678

Financial Instruments - Notiona

Financial Instruments - Notional Values of Outstanding Foreign Exchange Forward Contracts, Foreign Exchange Option Contracts and Interest Rate Swap Contracts (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Forward contracts (sell) [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	$ 449,371	$ 429,868
Forward contracts (sell) [member] | US Dollars [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	242,418	241,673
Forward contracts (sell) [member] | United Kingdom Pound Sterling [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	132,591	126,441
Forward contracts (sell) [member] | Euro [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	23,883	14,769
Forward contracts (sell) [member] | Australian Dollars [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	48,147	43,474
Forward contracts (sell) [member] | Others Currencies [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	2,332	3,511
Option contracts (sell) [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	275,268	214,468
Option contracts (sell) [member] | US Dollars [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	107,629	84,490
Option contracts (sell) [member] | United Kingdom Pound Sterling [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	116,401	94,094
Option contracts (sell) [member] | Euro [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	21,483	14,494
Option contracts (sell) [member] | Australian Dollars [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	28,828	19,412
Option contracts (sell) [member] | Others Currencies [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	927	1,978
Interest rate swap contracts [member] | US Dollars [member]
Disclosure of detailed information about financial instruments [line items]
Derivative, notional amount	$ 89,900	$ 118,000

Financial Instruments - Gain_(L

Financial Instruments - Gain/(Loss) Reclassified from Other Comprehensive Income into Consolidated Statement of Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of detailed information about financial instruments [line items]
Changes in fair value of cash flow hedges reclassified to profit/(loss)	$ 26,436	$ 24,777	$ 14,222
Income tax related to amounts reclassified into consolidated statement of income	(9,965)	(8,998)	(5,230)
Total	16,471	15,779	8,992
Revenue [member]
Disclosure of detailed information about financial instruments [line items]
Changes in fair value of cash flow hedges reclassified to profit/(loss)	11,231	7,952	7,941
Foreign exchange gain/(loss), net [member]
Disclosure of detailed information about financial instruments [line items]
Changes in fair value of cash flow hedges reclassified to profit/(loss)	15,766	16,896	$ 6,281
Finance expense [member]
Disclosure of detailed information about financial instruments [line items]
Changes in fair value of cash flow hedges reclassified to profit/(loss)	$ (561)	$ (71)

Financial Instruments - Foreign

Financial Instruments - Foreign Currency Risk from Non-derivative Financial Instruments (Detail) - Currency risk [member] - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and cash equivalents	$ 9,074	$ 4,816
Trade receivables	185,010	187,312
Unbilled revenue	18,118	12,658
Prepayments and other current assets	729	671
Other non-current assets	19	19
Trade payables	(116,213)	(136,282)
Provisions and accrued expenses	(2,983)	(2,719)
Pension and other employee obligations	(452)	(252)
Other liabilities	(11)	7
Net assets/ (liabilities)	93,291	66,230
US Dollars [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and cash equivalents	399	599
Trade receivables	100,002	98,713
Unbilled revenue	7,178	4,656
Prepayments and other current assets	428	428
Other non-current assets	3	3
Trade payables	(27,613)	(40,600)
Provisions and accrued expenses	(2,314)	(1,706)
Pension and other employee obligations	(134)	(56)
Other liabilities	(7)	(5)
Net assets/ (liabilities)	77,942	62,032
United Kingdom Pound Sterling [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and cash equivalents	4,735	253
Trade receivables	46,658	53,668
Unbilled revenue	3,209	1,241
Prepayments and other current assets	188	130
Trade payables	(64,070)	(71,039)
Provisions and accrued expenses	(291)	(504)
Other liabilities	(4)	(2)
Net assets/ (liabilities)	(9,575)	(16,253)
Indian Rupees [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Trade receivables	3,850	2,996
Prepayments and other current assets	10	3
Trade payables	(6,989)	(3,986)
Provisions and accrued expenses	(205)	(105)
Net assets/ (liabilities)	(3,334)	(1,092)
Australian Dollars [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and cash equivalents	2,991	2,606
Trade receivables	24,686	23,373
Unbilled revenue	643	3,062
Prepayments and other current assets	29	66
Trade payables	(16,093)	(19,205)
Provisions and accrued expenses		(128)
Net assets/ (liabilities)	12,256	9,774
Euro [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and cash equivalents	339	1,323
Trade receivables	7,289	5,370
Unbilled revenue	6,230	3,205
Prepayments and other current assets	63	30
Trade payables	(1,429)	(1,140)
Provisions and accrued expenses	(154)	(68)
Pension and other employee obligations	(12)	(31)
Net assets/ (liabilities)	12,325	8,689
Others Currencies [member]
Disclosure of nature and extent of risks arising from financial instruments [line items]
Cash and cash equivalents	610	35
Trade receivables	2,525	3,192
Unbilled revenue	858	494
Prepayments and other current assets	11	14
Other non-current assets	16	16
Trade payables	(19)	(312)
Provisions and accrued expenses	(19)	(208)
Pension and other employee obligations	(306)	(165)
Other liabilities		14
Net assets/ (liabilities)	$ 3,676	$ 3,080

Financial Instruments - Percent

Financial Instruments - Percentage of Revenue Generated from Top Customer and Top Five Customers (Detail)	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Top customer [Member]
Disclosure of major customers [line items]
Percentage of revenue generated from customers	6.80%	9.00%	10.90%
Top five customers [Member]
Disclosure of major customers [line items]
Percentage of revenue generated from customers	29.40%	32.10%	30.70%

Financial Instruments - Age-wis

Financial Instruments - Age-wise Break-up of Trade Receivables, Net of Allowances that are Past Due Beyond Credit Period (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of detailed information about financial instruments [line items]
Trade receivables	$ 71,952	$ 62,136
Allowances for doubtful account receivables	(564)	(1,713)
Trade receivables, net of allowances for doubtful accounts receivable	71,388	60,423
Neither past due nor impaired [member]
Disclosure of detailed information about financial instruments [line items]
Trade receivables	56,372	45,939
Past due but not impaired [member] | Past due 0-30 days [member]
Disclosure of detailed information about financial instruments [line items]
Trade receivables	9,578	8,260
Past due but not impaired [member] | Past due 31-60 days [member]
Disclosure of detailed information about financial instruments [line items]
Trade receivables	2,738	2,544
Past due but not impaired [member] | Past due 61-90 days [member]
Disclosure of detailed information about financial instruments [line items]
Trade receivables	834	1,174
Past due but not impaired [member] | Past due over 90 days [member]
Disclosure of detailed information about financial instruments [line items]
Trade receivables	1,866	2,506
Past due and impaired [member]
Disclosure of detailed information about financial instruments [line items]
Trade receivables	$ 564	$ 1,713

Financial Instruments - Contrac

Financial Instruments - Contractual Maturities of Financial Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of maturity analysis for financial liabilities [Line Items]
Long term debt (includes current portion)	$ 89,900	$ 118,000
Trade payables	19,703	14,239
Provision and accrued expenses	28,826	27,217
Other liabilities	13,834	20,764
Other employee obligations	59,347	46,701
Derivative financial instruments	8,755	4,783
Total	220,365	231,704
Less than 1 Year [member]
Disclosure of maturity analysis for financial liabilities [Line Items]
Long term debt (includes current portion)	28,100	28,100
Trade payables	19,703	14,239
Provision and accrued expenses	28,826	27,217
Other liabilities	10,680	9,338
Other employee obligations	59,347	46,701
Derivative financial instruments	6,466	3,947
Total	153,122	129,542
1-2 years [member]
Disclosure of maturity analysis for financial liabilities [Line Items]
Long term debt (includes current portion)	28,200	28,100
Other liabilities	3,154	8,195
Derivative financial instruments	2,289	836
Total	33,643	37,131
2-5 years [member]
Disclosure of maturity analysis for financial liabilities [Line Items]
Long term debt (includes current portion)	33,600	61,800
Other liabilities		3,231
Total	$ 33,600	$ 65,031

Financial Instruments - Cont100

Financial Instruments - Contractual Maturities of Financial Liabilities (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure Of Maturity Analysis For Financial Liabilities [Abstract]
Unamortised debt issuance cost	$ 769	$ 1,257

Financial Instruments - Summary

Financial Instruments - Summary of Net Cash Position (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Disclosure of detailed information about financial instruments [abstract]
Cash and cash equivalents	$ 99,829	$ 69,803	$ 41,854	$ 32,448
Investments	121,502	112,421
Long term debt (includes current portion)	(89,900)	(118,000)
Net cash position	$ 131,431	$ 64,224

Financial Instruments - Summ102

Financial Instruments - Summary of Net Cash Position (Parenthetical) (Detail) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Disclosure of detailed information about financial instruments [abstract]
Unamortized debt issuance cost	$ 769	$ 1,257

Pension and Other Employee O103

Pension and Other Employee Obligations - Summary of Pension and Other Employee Obligations (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current:
Salaries and bonus	$ 59,346	$ 46,701
Pension	1,189	770
Withholding taxes on salary and statutory payables	4,082	5,462
Total	64,617	52,933
Non-current:
Pension and other obligations	9,621	10,680
Total	$ 9,621	$ 10,680

Pension and Other Employee O104

Pension and Other Employee Obligations - Summary of Employee Benefits Costs (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of employee benefit expenses [Line Items]
Salaries and bonus	$ 405,665	$ 307,378	$ 272,017
Employee benefit plans: Defined contribution plan	11,684	10,265	7,458
Employee benefit plans: Defined benefit plan	3,042	2,639	2,184
Share-based compensation expense	30,565	23,036	17,919
Employee benefit costs	450,956	343,318	299,578
Cost of revenue [member]
Disclosure of employee benefit expenses [Line Items]
Share-based compensation expense	3,770	2,765	1,923
Employee benefit costs	329,289	249,701	217,098
Selling and marketing expenses [member]
Disclosure of employee benefit expenses [Line Items]
Share-based compensation expense	2,557	1,723	1,370
Employee benefit costs	31,373	24,717	22,336
General and administrative expenses [member]
Disclosure of employee benefit expenses [Line Items]
Share-based compensation expense	24,238	18,548	14,626
Employee benefit costs	$ 90,294	$ 68,900	$ 60,144

Pension and Other Employee O105

Pension and Other Employee Obligations - Contributions to Defined Contribution Plans (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	$ 11,684	$ 10,265	$ 7,458
India [member]
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	8,123	7,587	5,173
Philippines [member]
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	127	106	83
South Africa [member]
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	860	715	617
Sri Lanka [member]
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	625	661	612
UK [member]
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	670	780	681
USA [Member
Disclosure of geographical areas [Line Items]
Contributions to defined contribution plans	$ 1,279	$ 416	$ 292

Pension and Other Employee O106

Pension and Other Employee Obligations - Summary of Net Periodic Cost (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of defined benefit plans [abstract]
Service cost	$ 1,917	$ 2,188	$ 1,765
Past service cost	538
Interest on the net defined benefit liability	587	451	419
Net gratuity cost	$ 3,042	$ 2,639	$ 2,184

Pension and Other Employee O107

Pension and Other Employee Obligations - Summary of Net Defined Benefit Liability (Asset) (Detail) $ in Thousands	12 Months Ended
	Mar. 31, 2018USD ($)yr	Mar. 31, 2017USD ($)yr	Mar. 31, 2016USD ($)
Disclosure of net defined benefit liability (asset) [line items]
Service cost	$ 1,917	$ 2,188	$ 1,765
Past service cost	538
Interest cost	587	451	419
Accrued pension liability
Current	1,189	770
Non-current	8,871	10,030
Net amount recognized	10,060	10,800
Fair value of plan assets	(1,041)	(976)
Net surplus (deficit) in plan	$ 9,377	$ 7,790
Weighted average duration of defined benefit obligation (both funded and unfunded) | yr	4.8	8.3
Benefit obligations [member]
Disclosure of net defined benefit liability (asset) [line items]
Beginning of the year	$ 11,776	$ 8,450
Foreign currency translation	(118)	(30)
Service cost	1,917	2,188
Past service cost	538
Interest cost	657	513
Business combinations		95
Benefits paid	(1,160)	(1,283)
Actuarial (gain)/loss from changes in demographic assumptions	62	463
Actuarial (gain)/loss from changes in financial assumptions	(3,428)	(126)
Actuarial (gain)/loss from actual experience compared to assumptions	857	1,506
End of the year	11,101	11,776	8,450
Plan assets [member]
Disclosure of net defined benefit liability (asset) [line items]
Beginning of the year	976	849
Foreign currency translation	(5)	22
Expected return on plan assets	70	62
Actuarial (loss) /gain	(23)	39
Actual contributions	1,104	1,148
Benefits paid	(1,081)	(1,144)
End of the year	1,041	976	$ 849
Present value of funded defined benefit obligation [member]
Accrued pension liability
Present value of defined benefit obligation	10,418	8,766
Present value of unfunded defined benefit obligation [member]
Accrued pension liability
Present value of defined benefit obligation	$ 683	$ 3,010

Pension and Other Employee O108

Pension and Other Employee Obligations - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	$ 10,060	$ 10,800
Maximum limit of lump-sum gratuity payment	31	15
Past service cost	538
Amount of fund assets invested	1,041	976
Expected contributions for the year ending March 31, 2018	1,962
Life Insurance Corporation of India [member]
Disclosure of defined benefit plans [line items]
Amount of fund assets invested	4	4
Aviva Life Insurance Company Private Limited [member]
Disclosure of defined benefit plans [line items]
Amount of fund assets invested	$ 1,037	973
Unquoted government securities [member] | Life Insurance Corporation of India [member]
Disclosure of defined benefit plans [line items]
Fund assets, investment percentage	40.00%
Unquoted government securities [member] | Aviva Life Insurance Company Private Limited [member]
Disclosure of defined benefit plans [line items]
Fund assets, investment percentage	57.00%
Money market instruments [member] | Life Insurance Corporation of India [member]
Disclosure of defined benefit plans [line items]
Fund assets, investment percentage	60.00%
Money market instruments [member] | Aviva Life Insurance Company Private Limited [member]
Disclosure of defined benefit plans [line items]
Fund assets, investment percentage	43.00%
Discount rate [member]
Disclosure of defined benefit plans [line items]
Possible change in discount rates	Up to 1%
India [member]
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	$ 9,402	7,973
Philippines [member]
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	36	2,341
Sri Lanka [member]
Disclosure of defined benefit plans [line items]
Net amount recognized relating to defined benefit plan	$ 622	$ 486

Pension and Other Employee O109

Pension and Other Employee Obligations - Actuarial Assumptions For Gratuity Plans (Detail)	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of defined benefit plans [line items]
Expected rate of return on plan assets	7.30%	7.05%	7.35%
Bottom of range [member]
Disclosure of defined benefit plans [line items]
Rate of increase in compensation level	7.00%	7.00%	6.00%
Top of range [member]
Disclosure of defined benefit plans [line items]
Rate of increase in compensation level	10.00%	15.00%	8.00%
India [member]
Disclosure of defined benefit plans [line items]
Discount rate		7.05%	7.35%
India [member] | Bottom of range [member]
Disclosure of defined benefit plans [line items]
Discount rate	6.60%
India [member] | Top of range [member]
Disclosure of defined benefit plans [line items]
Discount rate	7.30%
Philippines [member]
Disclosure of defined benefit plans [line items]
Discount rate	3.10%	5.45%	4.75%
Sri Lanka [member]
Disclosure of defined benefit plans [line items]
Discount rate	10.00%	12.80%	12.30%

Pension and Other Employee O110

Pension and Other Employee Obligations - Sensitivity of Defined Benefit Obligation to a Change in Each Significant Actuarial Assumption (Detail)	Mar. 31, 2018
India [member] | Discount rate [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity of defined benefit obligation due to a possible increase in assumption	(7.30%)
Sensitivity of defined benefit obligation due to a possible decrease in assumption	0.70%
India [member] | Salary escalation [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity of defined benefit obligation due to a possible increase in assumption	3.60%
Sensitivity of defined benefit obligation due to a possible decrease in assumption	(3.50%)
Philippines [member] | Discount rate [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity of defined benefit obligation due to a possible increase in assumption	(1.40%)
Sensitivity of defined benefit obligation due to a possible decrease in assumption	1.50%
Philippines [member] | Salary escalation [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity of defined benefit obligation due to a possible increase in assumption	1.00%
Sensitivity of defined benefit obligation due to a possible decrease in assumption	(0.90%)
Sri Lanka [member] | Discount rate [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity of defined benefit obligation due to a possible increase in assumption	(3.40%)
Sensitivity of defined benefit obligation due to a possible decrease in assumption	0.50%
Sri Lanka [member] | Salary escalation [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Sensitivity of defined benefit obligation due to a possible increase in assumption	1.50%
Sensitivity of defined benefit obligation due to a possible decrease in assumption	(1.50%)

Pension and Other Employee O111

Pension and Other Employee Obligations - Sensitivity of Defined Benefit Obligation to a Change in Each Significant Actuarial Assumption (Parenthetical) (Detail)	Mar. 31, 2018
Discount rate [member] | India [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase in assumption	1.00%
Decrease in assumption	1.00%
Discount rate [member] | Philippines [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase in assumption	1.00%
Decrease in assumption	1.00%
Discount rate [member] | Sri Lanka [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase in assumption	1.00%
Decrease in assumption	1.00%
Salary escalation [member] | India [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase in assumption	1.00%
Decrease in assumption	1.00%
Salary escalation [member] | Philippines [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase in assumption	1.00%
Decrease in assumption	1.00%
Salary escalation [member] | Sri Lanka [member]
Disclosure of sensitivity analysis for actuarial assumptions [line items]
Increase in assumption	1.00%
Decrease in assumption	1.00%

Pension and Other Employee O112

Pension and Other Employee Obligations - Maturity Analysis of Defined Benefit Payments (Detail) $ in Thousands	Mar. 31, 2018USD ($)
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	$ 20,478
2019 [member]
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	2,230
2020 [member]
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	2,194
2021 [member]
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	2,179
2022 [member]
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	2,245
2023 [member]
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	2,370
More than 5 years [member]
Disclosure of Information About Maturity Profile of Defined Benefit Obligation [Line Items]
Defined benefit payments	$ 9,260

Provisions and Accrued Expen113

Provisions and Accrued Expenses - Summary of Provisions and Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current provisions and accrued expenses [abstract]
Accrued expenses	$ 28,826	$ 27,217
Total	$ 28,826	$ 27,217

Deferred Revenue - Summary of D

Deferred Revenue - Summary of Deferred Revenue (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current
Payments in advance of services	$ 557	$ 717
Advance billings	2,104	4,014
Others	247	747
Total	2,908	5,478
Non-current
Payments in advance of services	550	359
Advance billings	2
Others	19	19
Total	$ 571	$ 378

Other Liabilities - Summary of

Other Liabilities - Summary of Other Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Current
Withholding taxes and value added tax payables	$ 5,117	$ 5,356
Contingent consideration (Refer note 4(a), 4(b) and 4(c))	8,233	8,252
Deferred rent	800	677
Other liabilities	1,589	1,730
Total	15,739	16,015
Non-current
Deferred rent	6,544	5,292
Contingent consideration (Refer note 4(a), 4(b) and 4(c))	3,155	11,426
Other liabilities	1,963	1,751
Total	$ 11,662	$ 18,469

Share Capital - Additional Info

Share Capital - Additional Information (Detail)	Mar. 30, 2018USD ($)shares	Mar. 16, 2016USD ($)shares	Mar. 31, 2018USD ($)shares	Mar. 31, 2018GBP (£)£ / sharesshares	Mar. 31, 2017USD ($)shares	Mar. 31, 2017GBP (£)£ / sharesshares	Mar. 31, 2016USD ($)shares	Mar. 31, 2018$ / sharesshares	Mar. 16, 2018£ / shares	Mar. 31, 2017$ / sharesshares
Disclosure of classes of share capital [line items]
Authorized share capital shares				60,000,000		60,000,000		60,000,000		60,000,000
Par value per share | (per share)				£ 0.10		£ 0.10		$ 0.16		$ 0.16
Treasury shares [member]
Disclosure of classes of share capital [line items]
Number of shares outstanding				4,400,000		3,300,000	1,100,000	4,400,000		3,300,000
Ordinary shares [member]
Disclosure of classes of share capital [line items]
Authorized share capital amount | £				£ 6,100,000		£ 6,100,000
Authorized share capital shares				60,000,000		60,000,000		60,000,000		60,000,000
Par value per share | £ / shares				£ 0.10		£ 0.10
Number of shares outstanding				50,434,080		50,012,559		50,434,080		50,012,559
Preference shares [member]
Disclosure of classes of share capital [line items]
Authorized share capital shares				1,000,000		1,000,000		1,000,000		1,000,000
Par value per share | £ / shares				£ 0.10		£ 0.10
Number of shares outstanding				0		0		0		0
American depositary shares [member]
Disclosure of classes of share capital [line items]
Par value per share | £ / shares									£ 0.10
Number of ordinary shares represented by 1 American Depositary Shares		1
Number of shares repurchased			1,100,000	1,100,000	2,200,000	2,200,000
Shares repurchased value | $			$ 39,546,000		$ 64,224,000
Shares repurchased transaction costs | $			$ 17,000		33,000
Shares repurchased cancellation fees | $					$ 111,000		$ 55,000
American depositary shares [member] | Top of range [member]
Disclosure of classes of share capital [line items]
Number of shares authorized to be repurchased	3,300,000	3,300,000
Price for repurchase of shares | $	$ 100	$ 50
Duration of share repurchase program	36 months
American depositary shares [member] | Bottom of range [member]
Disclosure of classes of share capital [line items]
Price for repurchase of shares | $	$ 10	$ 10

Expenses by Nature - Summary of

Expenses by Nature - Summary of Expenses by Nature (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Expenses by nature [abstract]
Employee cost	$ 450,956	$ 343,318	$ 299,578
Repair payments	16,970	24,102	31,170
Facilities cost	89,037	75,383	67,689
Depreciation	19,954	16,903	15,435
Legal and professional expenses	22,972	15,902	13,227
Travel expenses	23,748	18,563	17,972
Others	38,886	33,526	30,035
Total cost of revenue, selling and marketing and general and administrative expenses	$ 662,523	$ 527,697	$ 475,106

Finance Expense - Summary of Fi

Finance Expense - Summary of Finance Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Analysis of income and expense [abstract]
Interest expense	$ 3,215	$ 424	$ 265
Interest rate swaps	561	71
Debt issue cost	488	52	13
Total	$ 4,264	$ 547	$ 278

Other Income, Net - Summary of

Other Income, Net - Summary of Other Income, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Analysis of income and expense [abstract]
Interest income	$ 3,693	$ 2,083	$ 1,197
Dividend income	3,570	4,131	5,039
Net gain arising on financial assets designated as FVTPL	3	6	41
Others, net	3,964	2,469	2,217
Total	$ 11,230	$ 8,689	$ 8,494

Share-based Payments - Addition

Share-based Payments - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2018USD ($)yr$ / sharesshares	Mar. 31, 2017USD ($)yr$ / sharesshares	Mar. 31, 2016USD ($)yr$ / sharesshares
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Number of shares available for future grants | shares	2,515,803
Number of shares issued upon exercise of share options and RSUs | shares	1,521,521	906,255	455,642
Total cash received from option exercised	$ 1,347,000	$ 8,941,000	$ 1,303,000
Share-based compensation expense	30,565,000	23,036,000	17,919,000
2006 Incentive award plan [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Aggregate intrinsic value of options exercised	$ 180,000	$ 2,697,000	$ 856,000
Total grant date fair value of options vested | shares	0	0	0
Total cash received from option exercised	$ 1,347,000	$ 8,941,000	$ 1,302,000
Number of options granted	0	0	0
Weighted average share price of options exercised	$ 30.44	$ 27.46	$ 28.19
Weighted average remaining contractual term | yr	0	0.10	0.54
2006 Incentive award plan [member] | Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Exercise price per options outstanding	$ 0	$ 29.21
2006 Incentive award plan [member] | Bottom of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Exercise price per options outstanding	$ 0	15.68
Share-based options [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share-based incentive plan - term	10 years
Share-based options [member] | Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Vesting period	Four years
Restricted share units (RSUs) [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share-based incentive plan - term	10 years
Restricted share units (RSUs) [member] | Top of range [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Vesting period	Four years
RSUs dependent on non-market performance condition [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Unrecognized compensation cost related to unvested other equity instruments	$ 6,893,000
Expected weighted average period for recognition of compensation cost other equity instruments | yr	2.7
Weighted average grant date fair value	$ 30.85	30.26	$ 25.16
Aggregate intrinsic value of share units exercised	34,339,000	9,991,000	10,294,000
Total grant date fair value of units vested	$ 16,931,000	$ 14,631,000	$ 6,824,000
Weighted average share price of share units exercised other equity instruments | $ / shares	$ 35.73	$ 29.08	$ 28.52
Number of RSUs granted	497,689	516,264
RSUs dependent on market performance condition [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Unrecognized compensation cost related to unvested other equity instruments	$ 963,000
Expected weighted average period for recognition of compensation cost other equity instruments | yr	1.3
Weighted average grant date fair value	$ 0	$ 12.56	$ 6.37
Additional cost as a result of modification in respect of modified share awards	1,185,000
Incremental cost recognized in the current year in respect of such modified RSUs	540,000	$ 24,000
Number of RSUs granted		74,400
RSUs related total shareholders return [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Unrecognized compensation cost related to unvested other equity instruments	3,585,000
Weighted average grant date fair value	36.52
Share-based compensation expense	$ 1,368,000
Number of RSUs granted	248,655
PSUs [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Vesting period	Three years
Unrecognized compensation cost related to unvested other equity instruments	$ 8,634,000
Weighted average grant date fair value	30.35	$ 31.12	20.12
Aggregate intrinsic value of share units exercised	17,737,000	4,237,000	532,000
Total grant date fair value of units vested	$ 8,696,000	$ 6,280,000	$ 0
Weighted average share price of share units exercised other equity instruments | $ / shares	$ 35.01	$ 29.89	$ 29.45
Expected weighted average period for recognition of compensation cost other equity instruments | yr	2.2
Number of RSUs granted	400,463	422,062
RSUs BBBEE Program In South Africa [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Vesting period	Four years
Share-based compensation expense	$ 547,000
Number of RSUs granted	32,050
Unamortized Share based compensation	$ 3,040,000

Share-based Payments - Summary

Share-based Payments - Summary of Share-based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share-based compensation expense	$ 30,565	$ 23,036	$ 17,919
Cost of revenue [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share-based compensation expense	3,770	2,765	1,923
Selling and marketing expenses [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share-based compensation expense	2,557	1,723	1,370
General and administrative expenses [member]
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Share-based compensation expense	$ 24,238	$ 18,548	$ 14,626

Share-based Payments - Movement

Share-based Payments - Movements in Number of Options Outstanding under 2006 Incentive Award Plan and Related Weighted Average Exercise Prices (Detail) - 2006 Incentive award plan [member]	12 Months Ended
	Mar. 31, 2018USD ($)yr	Mar. 31, 2017USD ($)yr	Mar. 31, 2016yr
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Beginning balance	117,179	739,618
Exercised	(48,227)	(425,941)
Lapsed	(68,952)	(196,498)
Ending balance		117,179
Weighted average exercise price, Beginning balance	$ 27.25	$ 23.34
Options exercisable	0
Weighted average exercise price, Exercised	$ 7.63	10.52
Weighted average exercise price, Lapsed	7.87	13.44
Weighted average exercise price, Ending balance		27.25
Aggregate intrinsic value, Beginning balance	163,000	5,419,000
Weighted average exercise price, Options exercisable	$ 0
Aggregate intrinsic value, Ending balance		$ 163,000
Weighted average remaining contract term (in years) | yr	0	0.10	0.54
Aggregate intrinsic value, Options exercisable	$ 0
Weighted average remaining contract term (in years), Options exercisable | yr	0

Share-based Payments - Movem123

Share-based Payments - Movements in Number of Restricted Share Units Dependent on Non-market Performance Condition Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values (Detail) - RSUs dependent on non-market performance condition [member]	12 Months Ended
	Mar. 31, 2018USD ($)yr	Mar. 31, 2017USD ($)yr	Mar. 31, 2016USD ($)yr
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Beginning balance	1,573,246	1,448,312
Granted	497,689	516,264
Exercised	(961,111)	(343,623)
Forfeited	(34,775)	(47,707)
Lapsed	(2,216)
Ending balance	1,072,833	1,573,246	1,448,312
Weighted average fair value, Beginning balance	$ 22.47	$ 19.25
Exercisable	309,312
Weighted average fair value, Granted	$ 30.85	30.26
Weighted average fair value, Exercised	21.45	20.18
Weighted average fair value, Forfeited	29.07	25.50
Weighted average fair value, Lapsed	23.47
Weighted average fair value, Ending balance	27.05	$ 22.47	$ 19.25
Weighted average fair value, exercisable	$ 20.90
Weighted average remaining contract term (in years) | yr	7.75	7.50	7.78
Weighted average remaining contract term (in years), exercisable | yr	5.94
Aggregate intrinsic value	$ 48,632,000	$ 45,011,000	$ 44,376,000
Aggregate intrinsic value, exercisable	$ 14,021,000

Share-based Payments - Movem124

Share-based Payments - Movements in Number of Restricted Share Units Dependent on Market Performance Condition Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values (Detail) - RSUs dependent on market performance condition [member]	12 Months Ended
	Mar. 31, 2018USD ($)yr	Mar. 31, 2017USD ($)yr	Mar. 31, 2016USD ($)yr
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Beginning balance	203,990	129,590
Granted		74,400
Exercised	0	0
Forfeited	0	0
Lapsed	0	0
Ending balance	203,990	203,990	129,590
Weighted average fair value, Beginning balance	$ 13.21	$ 4.44
Exercisable	0
Weighted average fair value, Granted		12.56
Weighted average fair value, Ending balance	$ 13.21	$ 13.21	$ 4.44
Weighted average remaining contract term (in years) | yr	7.10	8.10	8.53
Weighted average remaining contract term (in years), exercisable | yr	0
Aggregate intrinsic value	$ 9,247,000	$ 5,836,000	$ 3,971,000
Aggregate intrinsic value, exercisable	$ 0

Share-based Payments - Summa125

Share-based Payments - Summary of RSUs related to Total Shareholder's Return ('TSR') (Detail) - RSUs related total shareholders return [member]	12 Months Ended
	Mar. 31, 2018USD ($)yr
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Granted	248,655
Exercised	0
Forfeited	0
Lapsed	0
Ending balance	248,655
Exercisable	0
Weighted average fair value, Granted	$ 36.52
Weighted average fair value, Exercised	0
Weighted average fair value, Forfeited	0
Weighted average fair value, Lapsed	0
Weighted average fair value, Ending balance	36.52
Weighted average fair value, exercisable	$ 0
Weighted average remaining contract term (in years) | yr	9.08
Weighted average remaining contract term (in years), exercisable | yr	0
Aggregate intrinsic value	$ 11,272,000
Aggregate intrinsic value, exercisable	$ 0

Share-based Payments - Movem126

Share-based Payments - Movements in Number of Performance Share Units Outstanding under 2006 and 2016 Incentive Award Plan and Related Weighted Average Fair Values (Detail) - PSUs [member]	12 Months Ended
	Mar. 31, 2018USD ($)yr	Mar. 31, 2017USD ($)yr	Mar. 31, 2016USD ($)yr
Disclosure of terms and conditions of share-based payment arrangement [Line Items]
Beginning balance	1,184,852	951,588
Granted	400,463	422,062
Exercised	(506,660)	(141,741)
Forfeited	(18,681)	(47,057)
Ending balance	1,059,975	1,184,852	951,588
Weighted average fair value, Beginning balance	$ 21	$ 17.83
Exercisable	194,629
Weighted average fair value, Granted	$ 30.35	31.12
Weighted average fair value, Exercised	16.79	14.11
Weighted average fair value, Forfeited	29.38	26.27
Weighted average fair value, Ending balance	26.36	$ 21	$ 17.83
Weighted average fair value, exercisable	$ 18.14
Weighted average remaining contract term (in years) | yr	7.51	7.36	7.77
Weighted average remaining contract term (in years), exercisable | yr	5.86
Aggregate intrinsic value	$ 48,048,000	$ 33,899,000	$ 29,157,000
Aggregate intrinsic value, exercisable	$ 8,823,000

Income Taxes - Domestic and For

Income Taxes - Domestic and Foreign Source Component of Profit/(Loss) Before Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of income taxes [Line Items]
Profit before income taxes	$ 101,867	$ 55,293	$ 81,060
Domestic [member]
Disclosure of income taxes [Line Items]
Profit before income taxes	(4,439)	(5,342)	(4,121)
Foreign [member]
Disclosure of income taxes [Line Items]
Profit before income taxes	$ 106,306	$ 60,635	$ 85,181

Income Taxes - Provision for In

Income Taxes - Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of income taxes [Line Items]
Current taxes	$ 24,494	$ 25,785	$ 19,615
Deferred taxes	(9,063)	(8,255)	1,565
Provision for income taxes	15,431	17,530	21,180
Foreign [member]
Disclosure of income taxes [Line Items]
Current taxes	24,494	25,785	19,615
Deferred taxes	$ (9,063)	$ (8,255)	$ 1,565

Income Tax - Additional Informa

Income Tax - Additional Information (Detail) - USD ($)	Apr. 01, 2018	Mar. 21, 2009	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Disclosure of income taxes [Line Items]
Provision for income taxes			$ 15,431,000	$ 17,530,000	$ 21,180,000
Corporate tax rate			0.00%
Deferred tax liability derecognized			$ 11,812,000	20,800,000
Provision for income taxes			$ 9,368,000	$ 5,171,000	$ 5,072,000
Decrease in basic earnings loss per share			$ 0.19	$ 0.10	$ 0.10
Decrease in diluted earnings loss per share			$ 0.18	$ 0.10	$ 0.09
Unused tax losses for which no deferred tax asset recognized			$ 17,969,000
Temporary difference on which deferred tax liability has not been recognized amounts			494,571,000	$ 401,857,000	$ 301,043,000
Income tax reserve			12,370,000	12,432,000
Deposit of disputed amounts with tax authorities			13,416,000	12,031,000
Payment of service tax and related penalty		$ 5,341,000
Value Edge Research Services Private Limited [member]
Disclosure of income taxes [Line Items]
Deferred tax liability derecognized			1,686,000
Legal proceedings contingent liability [member]
Disclosure of income taxes [Line Items]
Estimated amount of additional taxes			45,002,000	44,573,000
Estimated amount of additional taxes, interest			13,897,000	$ 13,740,000
Domestic [member]
Disclosure of income taxes [Line Items]
Provision for income taxes			$ 0
Pune Mumbai and Chennai in India [member] | 2016 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption					100.00%
Pune Mumbai and Chennai in India [member] | 2017 - 2026 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption				50.00%
New Pune and Gurgaon in India [member] | Until 2019 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption						100.00%
New Pune and Gurgaon in India [member] | 2020 - 2029 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption						50.00%
New Pune and Gurgaon in India [member] | Until 2022 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption			100.00%
New Pune and Gurgaon in India [member] | 2023 - 2032 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption			50.00%
India [member]
Disclosure of income taxes [Line Items]
Percentage of minimum alternative tax			21.55%
Estimated amount of additional taxes			$ 43,583,000	$ 37,085,000
Estimated amount of additional taxes, interest			$ 17,234,000	$ 13,744,000
Costa Rica [Member] | 2018 - 2021 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption				50.00%
Iloilo and Alabang, Philippines [member] | Until 2021 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption				100.00%
Sri Lanka [member] | Changes in tax rates or tax laws enacted or announced [member]
Disclosure of income taxes [Line Items]
Corporate tax rate	14.00%
Alabang Philippines [member] | Until 2022 [member]
Disclosure of income taxes [Line Items]
Percentage of income tax exemption			100.00%
USA [Member | Changes in tax rates or tax laws enacted or announced [member]
Disclosure of income taxes [Line Items]
Tax effect from change in tax rate			$ (5,212,000)
Reduction in effective tax rate			5.12%
USA [Member | US [member]
Disclosure of income taxes [Line Items]
Corporate tax rate				35.00%
USA [Member | US [member] | Changes in tax rates or tax laws enacted or announced [member]
Disclosure of income taxes [Line Items]
Corporate tax rate			21.00%

Income Taxes - Income Taxes Rec

Income Taxes - Income Taxes Recognized Directly in Equity (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Current and deferred tax relating to items charged or credited directly to equity [abstract]
Excess tax deductions related to share-based payments	$ (685)	$ (270)	$ (229)
Excess tax deductions related to share-based payments	(1,135)	715	(688)
Total income tax recognized directly in equity	$ (1,820)	$ 445	$ (917)

Income Taxes - Income Taxes 131

Income Taxes - Income Taxes Recognized in Other Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Income tax relating to components of other comprehensive income [abstract]
Current taxes	$ 0	$ 0	$ 0
Unrealized gain/(loss) on cash flow hedging derivatives	(9,409)	6,921	(4,259)
Total income tax recognized directly in other comprehensive income	$ (9,409)	$ 6,921	$ (4,259)

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Estimated Income Tax to Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Major components of tax expense (income) [abstract]
Profit before income taxes	$ 101,867	$ 55,293	$ 81,060
Income tax expense at tax rates applicable to individual entities	32,702	21,765	28,067
Effect of:
Items not deductible for tax	221	455	771
Exempt income	(11,250)	(7,706)	(6,845)
Non tax deductible goodwill impairment		4,335
(Gain)/Loss in respect of which deferred tax (liability)/asset not recognized due to uncertainty and ineligibility to carry forward	324	(105)	259
Recognition of unutilized tax benefits / Unrecognized losses utilized		(1,220)	(294)
Temporary difference that will reverse during tax holiday period	22	1,580	30
Change in tax rate and law	(5,685)	78	(152)
Provision for uncertain tax position		(1,499)	2
State taxes	317	14	12
Due to acquisitions and merger	(1,686)
One time tax on undistributed earnings	266
Others, net	200	(167)	(670)
Provision for income taxes	$ 15,431	$ 17,530	$ 21,180

Income Taxes - Summary of Defer

Income Taxes - Summary of Deferred Taxes Arising from Temporary Differences and Unused Tax Losses (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	$ (4,113)	$ 20,733	$ 19,058
Additions due to acquisition during the year	(17)	(25,380)	(837)
Recognized in statement of income	9,063	8,255	(1,565)
Recognized in equity	1,135	(715)	688
Recognized in/ Reclassified from other comprehensive income	9,409	(6,921)	4,259
Foreign currency translation	106	(85)	(870)
Closing balance	15,583	(4,113)	20,733
Deferred tax liabilities [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	34,530	5,253	11,866
Additions due to acquisition during the year	6	24,577	837
Recognized in statement of income	(9,835)	(2,742)	(2,804)
Recognized in/ Reclassified from other comprehensive income	(9,409)	6,921	(4,259)
Foreign currency translation	237	521	(387)
Closing balance	15,529	34,530	5,253
Deferred tax liabilities [member] | Intangible assets other than goodwill [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	21,123	(712)	2,045
Additions due to acquisition during the year	6	24,577	837
Recognized in statement of income	(8,555)	(2,769)	(3,477)
Foreign currency translation	88	27	(118)
Closing balance	12,662	21,123	(712)
Deferred tax liabilities [member] | Unrealized gain/(loss) on cash flow hedging and investment [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	12,294	4,857	9,821
Recognized in statement of income	(1,280)	27	(436)
Recognized in/ Reclassified from other comprehensive income	(9,409)	6,921	(4,259)
Foreign currency translation	154	489	(269)
Closing balance	1,759	12,294	4,857
Deferred tax liabilities [member] | Others [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	1,113	1,108
Recognized in statement of income			1,108
Foreign currency translation	(5)	5
Closing balance	1,108	1,113	1,108
Deferred tax assets [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	30,417	25,986	30,924
Additions due to acquisition during the year	(11)	(803)
Recognized in statement of income	(772)	5,513	(4,369)
Recognized in equity	1,135	(715)	688
Foreign currency translation	343	436	(1,257)
Closing balance	31,112	30,417	25,986
Deferred tax assets [member] | Others [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	975	362	1,444
Recognized in statement of income	(661)	679	(1,179)
Foreign currency translation	14	(66)	97
Closing balance	328	975	362
Deferred tax assets [member] | Property and equipment [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	5,648	5,512	6,538
Additions due to acquisition during the year	(11)	(873)
Recognized in statement of income	1,623	932	(724)
Foreign currency translation	31	77	(302)
Closing balance	7,291	5,648	5,512
Deferred tax assets [member] | Net operating loss carryforward [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	5,722	3,684	4,304
Recognized in statement of income	(2,950)	2,026	(448)
Foreign currency translation	107	12	(172)
Closing balance	2,879	5,722	3,684
Deferred tax assets [member] | Accruals deductible on actual payment [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	5,641	5,352	4,201
Additions due to acquisition during the year		70
Recognized in statement of income	1,661	(1)	1,443
Foreign currency translation	122	220	(292)
Closing balance	7,424	5,641	5,352
Deferred tax assets [member] | Share-based payment arrangements [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	12,264	11,008	6,110
Recognized in statement of income	(702)	1,781	4,480
Recognized in equity	1,135	(715)	688
Foreign currency translation	73	190	(270)
Closing balance	12,770	12,264	11,008
Deferred tax assets [member] | Minimum alternate tax [member]
Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items]
Opening balance	167	68	8,327
Recognized in statement of income	257	96	(7,941)
Foreign currency translation	(4)	3	(318)
Closing balance	$ 420	$ 167	$ 68

Income Taxes - Deferred Tax Pre

Income Taxes - Deferred Tax Presented in Statement of Financial Position (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Deferred tax assets and liabilities [abstract]
Deferred tax assets	$ 27,395	$ 16,687
Deferred tax liabilities	(11,812)	(20,800)
Net deferred tax assets	$ 15,583	$ (4,113)

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Numerator:
Profit	$ 86,436	$ 37,763	$ 59,880
Denominator:
Basic weighted average ordinary shares outstanding	50,388,440	50,582,852	51,372,117
Dilutive impact of equivalent stock options and RSUs	2,527,160	2,357,456	2,267,553
Diluted weighted average ordinary shares outstanding	52,915,600	52,940,308	53,639,670

Earning Per Share - Additional

Earning Per Share - Additional Information (Detail) - shares	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Earnings per share [abstract]
Shares excluded from the calculation of diluted EPS options and RSUs since their effect is anti-dilutive	27,350	5,200	46,033

Related Party - List of the Com

Related Party - List of the Company's Subsidiaries (Detail) - Subsidiary	Mar. 15, 2017	Jun. 14, 2016	Mar. 31, 2018
WNS Global Services (UK) Limited [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			49.30%
WNS Global Services SA (Pty) Limited [Member] | WNS B-BBEE Staff Share Trust [Member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			10.00%
WNS Global Services SA (Pty) Limited [Member] | WNS Global Services (UK) Limited [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			90.00%
WNS Global Services Private Limited [member] | WNS Customer Solutions (Singapore) Private Limited [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			20.00%
WNS Global Services Private Limited [member] | WNS Global Services (UK) Limited [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			50.70%
WNS Global Services Private Limited [member] | WNS (Mauritius) Limited [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			80.00%
MTS HealthHelp Inc. [member] | HealthHelp Holdings LLC [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest	63.70%
WNS North America Inc. [member] | HealthHelp Holdings LLC [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest	36.30%
Value Edge Research Services Private Limited [member]
Disclosure of transactions between related parties [Line Items]
Number of subsidiaries acquired		3
WNS Assistance Limited [member] | WNS Legal Assistance LLP [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			98.75%
WNS Assistance (Legal) Limited [member] | WNS Legal Assistance LLP [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			1.25%
WNS Legal Assistance LLP [member] | Prettys Solicitors LLP [member]
Disclosure of transactions between related parties [Line Items]
Proportion of ownership interest			20.00%

Related Party - Key Management

Related Party - Key Management Personnel Compensation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of transactions between related parties [abstract]
Remuneration and short-term benefits	$ 6,614	$ 4,592	$ 4,671
Defined contribution plan	94	89	84
Other benefits	17	15	14
Share-based compensation expense	$ 17,677	$ 13,347	$ 8,674

Operating Segments - Additional

Operating Segments - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2018SegmentCustomer	Mar. 31, 2017	Mar. 31, 2016
Disclosure of operating segments [Line Items]
Number of reportable segment | Segment	2
WNS Global BPM segment [member]
Disclosure of operating segments [Line Items]
Number of clients individually accounted for more than 10% of total revenue | Customer	0
Percentage of revenue from top customer		9.00%	10.90%
Percentage of trade receivables of top customer		7.10%	10.00%

Operating Segments - Segment Re

Operating Segments - Segment Results for Operating Segments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of operating segments [Line Items]
Revenue	$ 757,956	$ 602,546	$ 562,179
Payments to repair centers	16,970	24,102	31,170
Revenue less repair payments (non-GAAP)	740,986	578,444	531,009
Depreciation	19,954	16,903	15,435
Other costs	580,061	449,142	399,613
Impairment of goodwill	0	21,673
Other income, net	(11,230)	(8,689)	(8,494)
Finance expense	4,264	547	278
Provision for income taxes	15,431	17,530	21,180
Segment profit/(loss)	132,506	81,338	102,997
Amortization of intangible assets	15,505	20,539	25,198
Share-based compensation expense	30,565	23,036	17,919
Profit/(loss)	86,436	37,763	59,880
Addition to non-current assets	32,538	111,733	31,858
Total assets, net of elimination	759,563	704,123	525,451
Total liabilities, net of elimination	264,607	289,057	117,262
External customers [member]
Disclosure of operating segments [Line Items]
Revenue	757,956	602,546	562,179
Operating segments [member]
Disclosure of operating segments [Line Items]
Segment operating profit/(loss)	140,971	90,726	115,961
Segment profit/(loss) before income taxes	147,937	98,868	124,177
Operating segments [member] | WNS global BPM [member]
Disclosure of operating segments [Line Items]
Revenue	722,600	557,983	509,268
Revenue less repair payments (non-GAAP)	722,600	557,983	509,268
Depreciation	19,682	16,598	15,090
Other costs	561,870	429,074	377,051
Segment operating profit/(loss)	141,048	112,311	117,127
Other income, net	(9,757)	(7,785)	(7,461)
Finance expense	4,065	547	278
Segment profit/(loss) before income taxes	146,740	119,549	124,310
Provision for income taxes	15,319	17,441	20,905
Segment profit/(loss)	131,421	102,108	103,405
Addition to non-current assets	32,337	111,280	30,757
Total assets, net of elimination	633,186	590,974	373,195
Total liabilities, net of elimination	181,627	214,155	36,660
Operating segments [member] | WNS global BPM [member] | External customers [member]
Disclosure of operating segments [Line Items]
Revenue	722,542	557,904	508,864
Operating segments [member] | WNS Auto Claims BPM [member]
Disclosure of operating segments [Line Items]
Revenue	35,414	44,642	53,315
Payments to repair centers	16,970	24,102	31,170
Revenue less repair payments (non-GAAP)	18,444	20,540	22,145
Depreciation	272	305	345
Other costs	18,249	20,147	22,966
Impairment of goodwill		21,673
Segment operating profit/(loss)	(77)	(21,585)	(1,166)
Other income, net	(1,473)	(904)	(1,033)
Finance expense	199
Segment profit/(loss) before income taxes	1,197	(20,681)	(133)
Provision for income taxes	112	89	275
Segment profit/(loss)	1,085	(20,770)	(408)
Addition to non-current assets	201	453	1,101
Total assets, net of elimination	126,377	113,149	152,256
Total liabilities, net of elimination	82,980	74,902	80,602
Operating segments [member] | WNS Auto Claims BPM [member] | External customers [member]
Disclosure of operating segments [Line Items]
Revenue	35,414	44,642	53,315
Inter segments [member]
Disclosure of operating segments [Line Items]
Revenue	(58)	(79)	(404)
Revenue less repair payments (non-GAAP)	(58)	(79)	(404)
Other costs	$ (58)	$ (79)	$ (404)

Operating Segments - External R

Operating Segments - External Revenue and Non-current Assets (Excluding Goodwill and Intangible Assets) by Geographic Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Disclosure of geographical areas [Line Items]
Revenue	$ 757,956	$ 602,546	$ 562,179
Non-current assets (excluding goodwill and intangible assets)	60,606	54,796
UK [member]
Disclosure of geographical areas [Line Items]
Revenue	258,863	248,588	264,889
Non-current assets (excluding goodwill and intangible assets)	756	1,228
USA [Member
Disclosure of geographical areas [Line Items]
Revenue	308,436	196,193	155,345
Non-current assets (excluding goodwill and intangible assets)	5,112	6,493
India [member]
Disclosure of geographical areas [Line Items]
Non-current assets (excluding goodwill and intangible assets)	26,167	21,944
South Africa [member]
Disclosure of geographical areas [Line Items]
Revenue	42,841	42,717	30,086
Non-current assets (excluding goodwill and intangible assets)	10,529	11,449
Philippines [member]
Disclosure of geographical areas [Line Items]
Non-current assets (excluding goodwill and intangible assets)	14,050	10,583
Rest of the world [member]
Disclosure of geographical areas [Line Items]
Revenue	34,021	28,501	36,819
Non-current assets (excluding goodwill and intangible assets)	3,992	3,099
Europe (excluding UK) [member]
Disclosure of geographical areas [Line Items]
Revenue	47,169	37,494	34,732
Australia [member]
Disclosure of geographical areas [Line Items]
Revenue	$ 66,626	$ 49,053	$ 40,308

Commitment and Contingencies -

Commitment and Contingencies - Future Minimum Lease Payments under Non-cancelable Operating Leases (Detail) $ in Thousands	12 Months Ended
	Mar. 31, 2018USD ($)
Disclosure of finance lease and operating lease by lessee [line items]
Minimum lease payments	$ 131,907
Less than 1 Year [member]
Disclosure of finance lease and operating lease by lessee [line items]
Minimum lease payments	27,572
1-3 years [member]
Disclosure of finance lease and operating lease by lessee [line items]
Minimum lease payments	47,115
3-5 years [member]
Disclosure of finance lease and operating lease by lessee [line items]
Minimum lease payments	29,783
More than 5 years [member]
Disclosure of finance lease and operating lease by lessee [line items]
Minimum lease payments	$ 27,437

Commitment and Contingencies143

Commitment and Contingencies - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Commitments and contingencies [line items]
Rental expense	$ 33,685	$ 27,712	$ 24,313
Commitments net	5,762	6,257
Bank guarantees	2,579	1,190
Restricted time deposits	$ 575	$ 355
Bottom of range [member]
Commitments and contingencies [line items]
Bank guarantees, remaining expiry term	1 year
Top of range [member]
Commitments and contingencies [line items]
Bank guarantees, remaining expiry term	5 years

Additional Capital Disclosur144

Additional Capital Disclosures - Summary of Capital Structure (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2015
Disclosure of objectives, policies and processes for managing capital [abstract]
Total equity attributable to the equity shareholders of the Company	$ 494,956	$ 415,066	$ 408,189	$ 389,106
As percentage of total capital	85.00%	78.00%
Long term debt	$ 89,900	$ 118,000
Long term debt	$ 89,900	$ 118,000
As percentage of total capital	15.00%	22.00%
Total capital (debt and equity)	$ 584,856	$ 533,066
Percentage of change in total equity attributable to the equity shareholders of the Company	19.00%
Percentage of change in long term debt	(24.00%)
Percentage of change in total debt	(24.00%)
Percentage of change in total capital (debt and equity)	10.00%

Additional Capital Disclosur145

Additional Capital Disclosures - Summary of Capital Structure (Parenthetical) (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017
Disclosure of objectives, policies and processes for managing capital [abstract]
Unamortised debt issuance cost	$ 769	$ 1,257

Additional Capital Disclosur146

Additional Capital Disclosures - Additional Information (Detail)	Mar. 31, 2018	Mar. 31, 2017
Disclosure of objectives, policies and processes for managing capital [abstract]
Borrowings percentage of outstanding share capital	15.00%	22.00%