PARENT ONLY FINANCIAL INFORMATION (Tables)

12 Months Ended

Dec. 31, 2016

PARENT ONLY FINANCIAL INFORMATION [Abstract]

	December 31,
	2015		2016
	RMB		RMB
ASSETS
Current assets:
Cash		6,275		43,770
Time deposits		397,388		242,795
Restricted time deposits		150,000		—
Prepaid expenses and other current assets		10,843		1,855
Total current assets		564,506		288,420
Investments and loans to subsidiaries		786,264		1,316,552
Total assets		1,350,770		1,604,972
LIABILITIESAND SHAREHOLDERS’ EQUITY
Current liabilities:
Accrued expenses and other current liabilities		6,522		3,409
Total current liabilities		6,522		3,409
Other non-current liabilities		5,634		3,343
Total liabilities		12,156		6,752

Commitments and contingencies		—		—

Shareholders’ equity:
Class A ordinary shares (US$0.001 par value,860,000,000 shares authorized, 44,914,538 and 48,735,228 shares issued, 43,988,425 and 47,160,248 shares outstanding as of December 31, 2015 and 2016, respectively)		276		302
Class B ordinary shares (US$0.001 par value, 40,000,000 shares authorized, 10,574,896 shares and 8,895,249 shares issued and outstanding as of December 31, 2015 and 2016, respectively)		98		86
Treasury shares (926,113 and 1,574,980 class A ordinary shares as of December 31, 2015 and 2016, respectively, at cost)		(49,355)		(93,761)
Additional paid-in capital		907,018		995,216
Accumulated other comprehensive income		30,232		58,204
Retained earnings		450,345		638,173
Total shareholders’ equity		1,338,614		1,598,220
Total liabilities and shareholders’ equity		1,350,770		1,604,972

Condensed Statements of Comprehensive Income

	Year Ended December 31,
	2014		2015		2016
	RMB		RMB		RMB
General and administrative expenses		(1,047)		(4,241)		(4,477)
Operating loss		(1,047)		(4,241)		(4,477)
Equity in income of subsidiaries		129,811		194,914		253,396
Foreign currency exchange gains (loss)		7,251		(31,923)		(4,753)
Interest income		14,059		17,610		8,027
Loss on foreign currency forward contract		—		—		(12,898)
Other income		1,776		2,400		2,559

Income before income taxes		151,850		178,760		241,854
Income tax expense		—		—		—

Net income		151,850		178,760		241,854
Other comprehensive income
Foreign currency translation adjustment, net of nil income tax		(2,896)		34,748		22,972
Unrealized holding gains on available for sale securities, net of RMB42 income taxes		—		—		5,235
Less: reclassification adjustment for gains on available for sale securities realized in net income, net of RMB42 income taxes		—		—		(235)
Comprehensive income		148,954		213,508		269,826

Condensed Statements of Cash Flows

	Year Ended December 31,
	2014		2015		2016
	RMB		RMB		RMB
Operating activities:
Net cash provided by (used in) operating activities		19,036		9,770		(10,272)

Investing activities:
Purchase of time deposits		(569,312)		(588,426)		(298,688)
Proceeds from maturity of time deposits		3,071		603,501		620,607
Investments made to subsidiaries		(104,662)		—		(198,137)

Net cash provided by (used in) investing activities		(670,903)		15,075		123,782

Financing activities:

Advances from a related party		—		1,432		—
Repayment of advances from a related party		—		(1,432)		—
Issuance of Class A ordinary shares upon the IPO		592,161		—		—
Issuance of Class A ordinary shares in private placement concurrent with the IPO		83,052		—		—
Issuance of Class A ordinary shares in connection with exercise of share options		1,518		22,456		20,388
Payment of dividends		—		—		(54,026)
Repurchase of treasury shares		—		(49,355)		(44,406)
Payment of IPO costs		(17,228)		—		—

Net cash provided by (used in) financing activities		659,503		(26,899)		(78,044)
Effect of foreign currency exchange rate changes on cash and cash equivalents		(27)		398		2,029
Net increase (decrease) in cash and cash equivalents		7,609		(1,656)		37,495
Cash and cash equivalents at beginning of year		322		7,931		6,275
Cash and cash equivalents at end of year		7,931		6,275		43,770

Non-cash investing and financing activities:
Conversion of Series A convertible redeemable preferred shares to Class B ordinary shares		3,648		—		—
Conversion of Series B convertible redeemable preferred shares to Class B ordinary shares		107,994		—		—
Conversion of Series C convertible redeemable preferred shares to Class B ordinary shares		592,849		—		—