General - Long Term Debt and Capital Lease Obligation (Details) - USD ($) $ in Thousands				9 Months Ended
	Oct. 30, 2017	Sep. 30, 2017	Sep. 22, 2017	Sep. 30, 2017	Sep. 30, 2016	Jul. 13, 2017	Jan. 10, 2017	Dec. 31, 2016	Jun. 27, 2016	Jul. 23, 2014
Long-term Debt and Capital Lease Obligations
Proceeds from issuance of debt				$ 949,239	$ 290,000
Debt disclosures
Capital lease obligations		$ 23,800		23,800				$ 26,000
Deferred loan issuance cost		8,300		$ 8,300				1,400
4.400% Senior Notes due 2024
Long-term Debt and Capital Lease Obligations
Aggregate principal amount of Senior Notes			$ 400,000
Stated interest rate (as a percent)			4.40%
Redemption price as a percentage of the principal amount being redeemed			100.00%
Proceeds from issuance of debt			$ 394,700
2014 Credit Facility
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity										$ 500,000
2014 Credit Facility | Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity										250,000
Debt disclosures
Revolving borrowings outstanding								175,000
2014 Credit Facility | Letter of Credit
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity										70,000
2014 Credit Facility | Term Loan
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity										$ 250,000
Weighted average interest rate (as a percent)				2.634%
2016 Credit Facility
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity									$ 200,000
2016 Credit Facility | Term Loan
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity									$ 200,000
Weighted average interest rate (as a percent)				2.39%
2017 Credit Facility | Letter of Credit
Debt disclosures
Letters of credit outstanding		5,000		$ 5,000				$ 33,700
2017 Credit Facility | Term Loan
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity							$ 200,000
Weighted average interest rate (as a percent)				2.691%
2017 Credit Agreement
Debt disclosures
Available borrowing capacity		395,000		$ 395,000
2017 Credit Agreement | Subsequent event
Long-term Debt and Capital Lease Obligations
Proceeds from issuance of debt	$ 135,000
2017 Credit Agreement | Revolving Loan borrowings
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity			400,000
Commitment commission (as a percent)				0.20%
Debt disclosures
Revolving borrowings outstanding		$ 0		$ 0
2017 Credit Agreement | Term Loan
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity			$ 350,000
Weighted average interest rate (as a percent)		2.74%
Long-term Debt, Fiscal Year Maturity
2017		$ 4,400		4,400
2018		17,500		17,500
2019		17,500		17,500
2020		17,500		17,500
2021		17,500		17,500
2022		275,600		275,600
2017 Credit Agreement | Prime rate
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			0.50%
2017 Credit Agreement | Overnight Federal Funds rate
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			0.50%
2017 Credit Agreement | Eurodollar rate for one month
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			1.00%
2017 Credit Agreement | Eurodollar rate for selected interest period
Long-term Debt and Capital Lease Obligations
Basis spread on variable rate (as a percent)			1.50%
SWH Bridge Facility
Long-term Debt and Capital Lease Obligations
Maximum borrowing capacity						$ 400,000
Standby Letters of Credit with The Bank Of Tokyo-Mitsubishi UFJ, Ltd. | Letter of Credit
Debt disclosures
Letters of credit outstanding		$ 21,500		$ 21,500