I am using OAUth authentication through connected apps. How can I get session timeout value(access token expiry time) as part of response during user authentication.

I am expecting "expires_in" attribute as well in the response. This link - *https://developer.salesforce.com/docs/atlas.en-us.api_rest.meta/api_rest/intro_understanding_user_agent_oauth_flow.htm* 
shows Salesforce appends token expire time in the response.

Response that I am getting- 
{"access_token":"00D19000000Eg9i!ARMAQPHFYb1d8i11SQMI5gGNgEQexfJrQR9IHuodm2qTr9LHdcmlm_jvYMVng5gs_CYcN5_s.YkJx6ysbG1SiGjiJQAdT_H3","refresh_token":"5Aep861FCftfNVCpAzffzyDwTRPXKAwLK6p_w_n99aGvRq_d_ccazXBodQhYbiXrg_HNY3im7WUq2wWpW5CaT_H","signature":"nYKG7fjDyZ71cSsjci2fc9jsr02kHIDDmSTMCFblCo4=","scope":"refresh_token full","id_token":"eyJraWQiOiIyMDIiLCJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.eyJhdF9oYXNoIjoiZlVRV2o4SldHSkh2M0NvOGpXMGlSdyIsInN1YiI6Imh0dHBzOi8vdGVzdC5zYWxlc2ZvcmNlLmNvbS9pZC8wMEQxOTAwMDAwMEVnOWlFQUMvMDA1MTkwMDAwMDE2VmlMQUFVIiwiYXVkIjoiM01WRzlOYzFxY1o3QmJaM3dZaFhzdl9jdU1YaHZ2Z25uZDlEaDA0NmpubXVNVkZLa0dyZy5uQ1hqLmhNZmRSX0dmdncuNE9ET1BRSjVCR1BPcmVxRSIsImlzcyI6Imh0dHBzOi8vdGVzdC5zYWxlc2ZvcmNlLmNvbSIsImV4cCI6MTQ2ODMzODAwMSwiaWF0IjoxNDY4MzM3ODgxfQ.SyYrPYnCI8DgB94NDd37lZ-n3w2EKLcoCJyfymvCjNzilVch6muOGAfSuItgWwtRyAseRiIc5LPVZN5hCkQUA6DDM2XxHBKDiu-INqX6_8CfAjB4Is7Y7K6xwUE9FGUbVhnx2O-H8BQqu1g0etCdK_dZTce1O1CCriQ00Y8VocUwWorslyaElLpGv3t3ZL2VyKeoYLXScK8atU4s4EuppV1dsLpRxsv2ex_956LIVLtkst57L9We6DN-5dhw-pkI_q3YFdKbLkawJsYQBCAGfskpCX6Cr1C8Nv88WbY83Zd_MqwB8wPQWQk56-sUk7EO5lh8JJQ3I6aZNjidO6hJSUvNzXV3Vp_YuCWVeogEqWDA7c5oFvXE_HynU7AOwPL_IxJbGe6QNFE6B_gl3pJZtAOkNx_dzHsXn70GOADoJ_WqW_BPAP3wzFpmjDdVnnZcZ3UTLGo6VCGk0F8w0k7Hfyjp34r-yiepdFe98lukusYM7mtkGKsW3ok7qaQ_CINu8hljGJsKoLer47DUGQ84xenFZ6kHLN978i4b_SciWj4KoY4RkV8VBPFfEJfE0N4gRu2xRb55MVKu3PMBEWUkiE0kMiW0-LiBSrmYyYAsyqReoB9048yUm7a7lzN55RfVHNSSZz58C6Y0aTlMjWPFtBoIuvHt7THvqisvswDXSdg","instance_url":"","id":"https://test.salesforce.com/id/00D19000000Eg9iEAC/005190000016ViLAAU","token_type":"Bearer","issued_at":"1468337881077"}