Long-Term Debt - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	6 Months Ended			1 Months Ended													1 Months Ended	3 Months Ended			1 Months Ended		1 Months Ended						1 Months Ended	3 Months Ended	6 Months Ended				6 Months Ended				6 Months Ended
	May 14, 2013	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012	May 31, 2013 Interest Rate Swaps [Member] Swap	Aug. 23, 2012 Interest Rate Swaps [Member] Swap	Jun. 30, 2013 Interest Rate Swaps [Member] Swap	May 13, 2013 Interest Rate Swaps [Member] Minimum [Member]	May 13, 2013 Interest Rate Swaps [Member] Maximum [Member]	May 31, 2013 Interest Rate Swap One [Member]	Aug. 23, 2012 Interest Rate Swap One [Member]	May 31, 2013 Interest Rate Swap Two [Member]	Aug. 23, 2012 Interest Rate Swap Two [Member]	Jun. 30, 2013 Blackstone and Affiliates [Member]	Apr. 24, 2013 Blackstone and Affiliates [Member]	Apr. 05, 2013 Revolving Credit Agreement [Member]	Apr. 04, 2013 Revolving Credit Agreement [Member]	Apr. 24, 2013 Term Loan B [Member]	Mar. 30, 2012 Term Loan B [Member]	Apr. 05, 2013 Term Loan B [Member]	Dec. 31, 2012 Term Loan B [Member]	May 14, 2013 Term B-2 Loans [Member]	Jun. 30, 2013 Term B-2 Loans [Member]	May 14, 2013 Term B-2 Loans [Member] Federal Funds Rate [Member]	May 14, 2013 Term B-2 Loans [Member] Base Rate Loan [Member]	May 14, 2013 Term B-2 Loans [Member] LIBOR Rate Loan [Member]	Apr. 05, 2013 Revolving Credit Agreement [Member]	Jun. 30, 2013 Revolving Credit Agreement [Member]	Dec. 31, 2012 Revolving Credit Agreement [Member]	Apr. 24, 2013 Senior Notes [Member]	Jun. 30, 2013 Senior Notes [Member]	Jun. 30, 2013 Senior Notes [Member]	Apr. 05, 2013 Senior Notes [Member]	Dec. 31, 2012 Senior Notes [Member]	Mar. 30, 2012 Senior Notes [Member]	Jun. 30, 2013 Senior Notes [Member] Prior to December 1, 2014 [Member]	Jun. 30, 2013 Senior Notes [Member] Prior to December 1, 2014 [Member] Equity Offering [Member]	Jun. 30, 2013 Senior Notes [Member] On or After December 1, 2014 [Member]	Jun. 30, 2013 Senior Notes [Member] On or After December 1, 2015 [Member]	Jun. 30, 2013 Second Supplemental Indenture [Member]	Jun. 30, 2013 Second Supplemental Indenture [Member] Revised [Member]	Apr. 05, 2013 Term Loan A [Member]	Dec. 31, 2012 Term Loan A [Member]	Apr. 05, 2013 Fourth Supplemental Indenture [Member]
Debt Instrument [Line Items]
Repayment of portion of Term Loan B																		$ 37,000
Repayment of Senior Notes																														140,000
Redemption price for Senior Notes																														111.00%						100.00%	111.00%	105.50%	102.75%
Redemption premium included in early extinguishment of debt																															15,400	15,400
Write-off of discounts and deferred financing costs																																5,500
Proceeds from issuance of debt		1,455	487,163																500,000
Senior secured revolving credit facility existing																192,500	172,500
Number of days used to calculate maturity																											91 days
Aggregate principal amount at maturity																				150,000													50,000									50,000
Senior secured revolving credit facility maturity date																											The new senior secured revolving credit facility will mature on the earlier of (a) April 24, 2018 or (b) the 91st day prior to the earlier of (1) the maturity date with respect to Term A Loans with an aggregate principal amount greater than $50,000 outstanding, (2) the maturity date with respect to the Term B Loans with an aggregate principal amount greater than $150,000 outstanding, (3) the maturity date of Senior Notes (also referred to as “Mezzanine Debt”) with an aggregate principal amount greater than $50,000 outstanding and (4) the maturity date of any indebtedness incurred to refinance any of the Term A or Term B Loans or the Mezzanine Debt.
Aggregate principal amount of debt instrument																						1,405,000
Interest rate, description																						Borrowings under the Term B-2 Loans bear interest, at SEA's option, at a rate equal to a margin over either (a) a base rate determined by reference to the higher of (1) the Bank of America's prime lending rate and (2) the federal funds effective rate plus 1/2 of 1% or (b) a LIBOR rate determined by reference to the British Bankers Association ("BBA") LIBOR rate for the interest period relevant to such borrowing
Margin for Term Loans																								0.50%	1.25%	2.25%
Floor rate																									1.75%	0.75%
Basis point step-down in applicable margin																						The applicable margin for the Term B-2 Loans (under either a base rate or LIBOR rate) is subject to one 25 basis point step-down upon achievement by SEA of a certain leverage ratio.
Basis point step down on applicable margin upon achievement of certain leverage ratio																						25
LIBOR interest rate		3.00%
Revolving Credit Facility in aggregate principal amount	350,000
Percent of original principal amount on effective date used to calculate aggregate annual amount which will amortize in equal quarterly installments																						1.00%
Term loan maturity date																						May 14, 2020
Maximum first lien secured net leverage ratio	3.50
Written off of debt issuance cost	11,500
Capitalized fees		13,961	7,024
Deferred financing costs, net of accumulated amortization		36,272		44,103
Amounts of outstanding long-term debt (In USD)		1,665,000		1,845,774																	1,293,774		1,405,000								260,000	260,000		400,000									152,000
Outstanding letters of credit (In USD)		18,500
Termination fee paid														46,300	46,300
Debt instrument interest rate																															11.00%	11.00%			13.50%
Senior Notes redemption percentage																																					35.00%
Percent of Senior Notes principle amount used to calculate applicable premium																																				1.00%
Redemption of Senior Notes description																																Prior to December 1, 2014, the Company may redeem some or all of the Senior Notes at a price equal to 100% of the principal amount of the Senior Notes redeemed plus the Applicable Premium as of, and accrued and unpaid interest to, the redemption date, subject to the right of the holders of record on the relevant record date to receive interest due on the relevant interest payment date. The “Applicable Premium” is defined as the greater of (1) 1.0% of the principal amount of the Senior Notes and (2) the excess, if any, of (a) the present value at such redemption date of (i) the redemption price of the Senior Notes at December 1, 2014 plus (ii) all required interest payments due on the Senior Notes through December 1, 2014 (excluding accrued but unpaid interest to the redemption date), computed using a discount rate equal to the Treasury Rate plus 50 basis points over (b) the principal amount of the Senior Notes.
Basis points over the principal balance of the Senior Notes																																				50
Debt instrument covenant leverage ratio																																The Second Supplemental Indenture also increased the minimum covenant leverage ratio from 2.75 to 1.00 to 3.00 to 1.00.
Minimum covenant leverage ratio																																								2.75	3.00
Increase in debt																																												20,000
Maximum termination fee payment allowed for the Advisory Agreement termination																																												50,000
Number of interest rate swap held					2	2	2
Notional amount of Interest rate swap					550,000	550,000	550,000			275,000	275,000	275,000	275,000
Maturity of interest rate swap					Sep. 30, 2016	Sep. 30, 2016
Fixed rate of interest on swaps						1.247%		1.049%	1.051%
Cash paid for interest		$ 47,881	$ 51,175