Study to Investigate Idelalisib in Combination With Chemotherapeutic Agents, Immunomodulatory Agents and Anti-CD20 Monoclonal Antibody (mAb) in Participants With Relapsed or Refractory Indolent B-cell Non-Hodgkin's Lymphoma, Mantle Cell Lymphoma or Chronic Lymphocytic Leukemia

Key Inclusion Criteria: * Age ≥ 18 * Previously treated with relapsed or refractory disease (refractory defined as not responding to a standard regimen or progressing within 6 months of the last course of a standard regimen) * Disease status requirement: * For CLL patients, symptomatic disease that mandates treatment as defined by the International Workshop on Chronic Lymphocytic Lymphoma (IWCLL) 2008 criteria * For indolent NHL and MCL patients, measurable disease by CT scan defined as at least 1 lesion that measures \> 2 cm in a single dimension * WHO performance status of ≤ 2 * For men and women of child-bearing potential, willing to use adequate contraception (ie, latex condom, cervical cap, diaphragm, abstinence, etc.) for the entire duration of the study. * For Cohort 7 only: Women of child bearing potential must have 2 negative pregnancy tests prior to starting lenalidomide. * Able to provide written informed consent Key Exclusion Criteria: * Is not a good candidate to receive any of the drugs administered in the study for a given disease (idelalisib, bendamustine, rituximab, ofatumumab, fludarabine, everolimus, bortezomib, or chlorambucil), according to the clinical judgment of the investigator * Patients with atypical immunophenotype with t(11:14) translocation or cyclin D1 over-expression (CLL patients only) * Had radiotherapy, radioimmunotherapy, biological therapy, chemotherapy, or treatment with an investigational product within 4-weeks prior to the baseline disease status tests * Had treatment with a short course of corticosteroids for symptom relief within 1-week prior to the baseline disease status tests * Has had an allogeneic hematopoietic stem cell transplant * Has known active central nervous system involvement of the malignancy * Is pregnant or nursing * Has active, serious infection requiring systemic therapy. Patients may receive prophylactic antibiotics and antiviral therapy at the discretion of the investigator * Has absolute neutrophil count (ANC) \< 1000/µL, unless it is related to underlying CLL, MCL or indolent NHL, the latter documented by \> 50% infiltration of bone marrow by tumor cells * Has platelet count \< 75000/µL, unless it is related to underlying CLL, MCL, or iNHL, the latter documented by \> 50% infiltration of bone marrow by tumor cells * Has serum creatinine ≥ 2.0 mg/dL * For Cohort 7 only: Has creatinine clearance \< 60 mL/min * Has serum bilirubin ≥ 2 mg/dL (unless due to Gilbert's syndrome) for patients with iNHL or CLL; for patients with MCL, serum bilirubin ≥ 1.5 x upper limit of normal * Has serum aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ≥ 2 x upper limit of normal * Has Child-Pugh Class B or C hepatic impairment * Has a positive test for HIV antibodies * Has active hepatitis B or C (confirmed by RNA test). Patients with serologic evidence of prior exposure are eligible. * Prior treatment with idelalisib Note: Other protocol defined Inclusion/Exclusion criteria may apply.