Stockholders' equity - ASR - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended
	May 04, 2021	May 27, 2020	Jan. 30, 2020	Mar. 31, 2021	Mar. 31, 2020	May 03, 2021
Stockholders Equity Note
Common stock purchases				$ 3,942	$ 502,801
Treasury stock
Stockholders Equity Note
Common stock purchases				$ 3,942	425,735
Capital surplus
Stockholders Equity Note
Common stock purchases					$ 77,066
Accelerate Share Repurchase
Stockholders Equity Note
Stock repurchase program authorized amount			$ 500,000
Initial shares received as part of an accelerated share repurchase program			7,055,919
Accelerate Share Repurchase | Treasury stock
Stockholders Equity Note
Common stock purchases			$ 400,000
Accelerate Share Repurchase | Capital surplus
Stockholders Equity Note
Common stock purchases			$ (100,000)
Accelerate Share Repurchase | Subsequent event
Stockholders Equity Note
Stock repurchase program authorized amount						$ 350,000
Accelerated share repurchases settlement receipt	$ 350,000
Initial shares received as part of an accelerated share repurchase program	3,785,831
Accelerate Share Repurchase | Subsequent event | Treasury stock
Stockholders Equity Note
Common stock purchases	$ 280,000
Accelerate Share Repurchase | Subsequent event | Capital surplus
Stockholders Equity Note
Common stock purchases	$ (70,000)
Accelerate Share Repurchase | COVID-19
Stockholders Equity Note
Stock Repurchased During Period Shares				11,819,135
Accelerated share repurchases price paid per share				$ 42.3043
Common Shares Repurchased Accelerated Share Repurchase Agreements		4,763,216