Independence Blue Cross, the Philadelphia region's largest health insurer, has offered a "voluntary severance program" to about 900 employees in certain business units with at least 15 years of service as of Dec. 31.

The company told eligible employees in an email Thursday that it was offering the program from a position of financial strength. Independence had $67 million in net income on $16.7 billion in revenue last year.

"This approach will allow us to reshape our business while offering benefits to associates who may be considering a change, whether to explore new business opportunities or focus on personal interests," the email, signed by chief executive Daniel J. Hilferty, said.

The email described a "dynamic market, with increased competition, a growing shift from fully insured to self-insured business, significant political uncertainty, and the need for continued investment in consumer capabilities."

Vast areas of Independence, which employs more than 10,000, are excluded from the buyout offer. Those businesses include the unit that handles administration of health benefits for self-insured employers; AmeriHealth Caritas, a Medicaid managed-care company that operates in 17 states; and Tandigm Health, a new subsidiary that coordinates care with primary-care physicians.

Basis terms of the buyout offer are three weeks of weekly base pay for every year of services and continued medical benefits during the severance  period. The deadline to apply is Nov. 16.