Financing (Tables)

3 Months Ended

Mar. 31, 2019

Debt Disclosure [Abstract]

Outstanding financing facilities

									March 31, 2019		December 31, 2018
Revolving Credit Facility, weighted-average variable interest rate of							3.740%		$	330,000	$	287,000
$	500	million,	4.875	%	Senior Notes due 2021,	effective interest rate of 4.952%		(1)	498,573		498,371
$	300	million,	4.625	%	Senior Notes due 2021,	effective interest rate of 4.644%		(2)	299,315		299,244
$	300	million,	3.800	%	Senior Notes due 2022,	effective interest rate of 3.845%		(3)	298,666		298,574
$	300	million,	3.850	%	Senior Notes due 2023,	effective interest rate of 3.851%		(4)	298,881		298,821
$	500	million,	3.550	%	Senior Notes due 2026,	effective interest rate of 3.570%		(5)	496,354		496,240
$	750	million,	3.600	%	Senior Notes due 2027,	effective interest rate of 3.619%		(6)	744,020		743,868
$	500	million,	4.350	%	Senior Notes due 2028,	effective interest rate of 4.383%		(7)	495,112		495,004
Long-term debt									$	3,460,921	$	3,417,122

⁽¹⁾  Net of unamortized discount of $0.6 million as of March 31, 2019, and $0.7 million as of December 31, 2018, and debt issuance costs of $0.8 million as of March 31, 2019, and $0.9 million as of December 31, 2018.

⁽²⁾  Net of unamortized discount of $0.1 million as of March 31, 2019, and December 31, 2018, and debt issuance costs of $0.6 million as of March 31, 2019, and December 31, 2018.

⁽³⁾  Net of unamortized discount of $0.4 million as of March 31, 2019, and $0.5 million as of December 31, 2018, and debt issuance costs of $0.9 million as of March 31, 2019, and $1.0 million as of December 31, 2018.

⁽⁴⁾  Net of unamortized discount of less than $0.1 million as of March 31, 2019, and December 31, 2018, and debt issuance costs of $1.1 million as of March 31, 2019, and $1.2 million as of December 31, 2018.

⁽⁵⁾  Net of unamortized discount of $0.6 million as of March 31, 2019, and December 31, 2018, and debt issuance costs of $3.0 million as of March 31, 2019, and $3.1 million as of December 31, 2018.

⁽⁶⁾  Net of unamortized discount of $1.0 million as of March 31, 2019, and $1.1 million as of December 31, 2018, and debt issuance costs of $4.9 million as of March 31, 2019 and $5.1 million as of December 31, 2018.

⁽⁷⁾ 

Net of unamortized discount of $1.2 million as of March 31, 2019, and $1.3 million as of December 31, 2018, and debt issuance costs of $3.6 million as of March 31, 2019, and $3.7 million as of December 31, 2018.