Income Taxes

The following table presents income tax expense and the effective tax rate:



	Three Months Ended September 30,						Nine Months Ended September 30,
	2016			2015			2016			2015
	(Dollars in thousands)
Income tax expense	$	34,692		$	29,486		$	104,227		$	88,565
Effective tax rate	23		%	24		%	24		%	24		%

The effective tax rate for the three and nine months ended September 30, 2016 and 2015 was lower than the statutory federal rate of 35% primarily due to tax benefits from foreign income taxed at lower rates, partially offset by state income taxes.

Deferred tax liabilities as of September 30, 2016 reflect the use of a portion of U.S. foreign tax credits during the nine months ended September 30, 2016, and an increase in the deferred tax liability related to the Subordinated Convertible Debentures.