Acquisition charges (Tables)

9 Months Ended

Sep. 30, 2014

Business Combination, Separately Recognized Transactions [Abstract]

Acquisition charges

These acquisition charges are as follows:

	For Three Months Ended September 30,				For Nine Months Ended September 30,
	2014		2013		2014		2013
Amortization of intangible assets	$	80	$	81	$	239	$	244
Stock-based compensation	3		3		9		8
Retention bonuses	—		2		—		5
Acquisition charges	$	83	$	86	$	248	$	257