Study to Evaluate Safety, Tolerability, and Pharmacokinetics of Idelalisib in Japanese Participants With Relapsed or Refractory Indolent B-Cell Non-Hodgkin Lymphomas (iNHL) or Chronic Lymphocytic Leukemia (CLL)

Key Inclusion Criteria:

* Participants with mature B-cell malignancies of iNHL including follicular lymphoma, small lymphocytic lymphoma, lymphoplasmacytic lymphoma, marginal zone lymphoma, and CLL by World Health Organization classification
* Must have been born in Japan and must not have lived outside of Japan for \> 1 year in the 5 years prior to Day 1
* Must be able to trace maternal and paternal ancestry of parents and grandparents as Japanese
* Must have been previously treated with at least 1 regimen for iNHL or CLL and currently require treatment
* Discontinuation of all therapy (including radiotherapy, chemotherapy, immunotherapy, or investigational therapy) for the treatment of iNHL or CLL ≥ 4 weeks prior to Day 1
* Eastern Cooperative Oncology Group performance status of 0 or 1
* Required baseline laboratory data (within 4 weeks prior to Day 1)
* A negative serum pregnancy test for female participants of childbearing potential
* Males and females of childbearing potential who engage in heterosexual intercourse must agree to use protocol-specified method(s) of contraception.
* In the judgment of the investigator, participation in the protocol offers an acceptable benefit-to-risk ratio when considering current disease status, medical condition, and the potential benefits and risks of alternative treatments for the individual's disease.

Key Exclusion Criteria:

* Known histological transformation to an aggressive histology
* Known presence of myelodysplastic syndrome
* History of iNHL or CLL with central nervous system involvement
* Life expectancy \< 120 days as per investigator assessment
* History of a nonlymphoid malignancy with the following exceptions:

  * the malignancy has been in remission without treatment for ≥ 5 years prior to Day 1, or
  * carcinoma in situ of the cervix, or
  * adequately treated basal or squamous cell skin cancer or other localized nonmelanoma skin cancer, or
  * surgically treated low-grade prostate cancer, or
  * ductal carcinoma in situ of the breast treated with lumpectomy alone
* On-going drug-induced liver injury, alcoholic liver disease, nonalcoholic steatohepatitis, primary biliary cirrhosis, extrahepatic obstruction caused by cholelithiasis, cirrhosis of the liver, or portal hypertension
* History or diagnosis of pneumonitis or interstitial lung disease.
* On-going inflammatory bowel disease
* Pregnancy or breastfeeding
* History of prior allogeneic hematopoietic stem cell or solid organ transplantation
* Concurrent participation in another therapeutic clinical trial
* Prior or on-going clinically significant illness, medical condition, surgical history, physical finding, electrocardiogram finding, or laboratory abnormality that, in the investigator's opinion, could adversely affect the safety of the individual or impair the assessment of study results.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.