Derivatives (Fair Value of Derivative Instruments) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Fair value	$ (0.1)	[1]	$ (9.7)	[1]
Interest Rate Swap One [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	60.0
Derivative, Fair value			(0.2)	[1]
Derivative, Interest Rate	1.74%
Derivative, Maturity Date	Mar. 11, 2013
Interest Rate Swap Two [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	200.0
Derivative, Fair value			(1.0)	[1]
Derivative, Interest Rate	2.96%
Derivative, Maturity Date	Mar. 11, 2013
Interest Rate Swap Three [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	40.0
Derivative, Fair value			(0.1)	[1]
Derivative, Interest Rate	1.82%
Derivative, Maturity Date	Mar. 11, 2013
Interest Rate Swap Four [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	65.0
Derivative, Fair value			(1.5)	[1]
Derivative, Interest Rate	3.60%
Derivative, Maturity Date	Sep. 09, 2013
Interest Rate Swap Five [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	68.0
Derivative, Fair value			(1.6)	[1]
Derivative, Interest Rate	3.69%
Derivative, Maturity Date	Sep. 09, 2013
Interest Rate Swap Six [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	35.0
Derivative, Fair value			(1.4)	[1]
Derivative, Interest Rate	3.73%
Derivative, Maturity Date	Sep. 09, 2013
Interest Rate Swap Seven [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	55.0
Derivative, Fair value			(1.3)	[1]
Derivative, Interest Rate	2.90%
Derivative, Maturity Date	Nov. 29, 2013
Interest Rate Swap Eight [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	48.0
Derivative, Fair value			(1.2)	[1]
Derivative, Interest Rate	2.90%
Derivative, Maturity Date	Nov. 29, 2013
Interest Rate Swap Nine [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	25.0
Derivative, Fair value	(0.3)	[1]	(0.5)	[1]
Derivative, Interest Rate	1.10%
Derivative, Maturity Date	Jul. 31, 2016
Interest Rate Swap Ten [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	28.1
Derivative, Fair value	(0.5)	[1]	(0.9)	[1]
Derivative, Interest Rate	1.38%
Derivative, Maturity Date	Jan. 02, 2017
Interest Rate Swap Eleven [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	34.9
Derivative, Fair value	0.2	[1]
Derivative, Interest Rate	3.72%
Derivative, Maturity Date	Dec. 01, 2017
Interest Rate Swap Twelve [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	7.6
Derivative, Fair value	0.1	[1]
Derivative, Interest Rate	1.00%
Derivative, Maturity Date	Jan. 01, 2018
Interest Rate Swap Thirteen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	48.0
Derivative, Fair value	0.2	[1]
Derivative, Interest Rate	1.12%
Derivative, Maturity Date	Jan. 01, 2018
Interest Rate Swap Fourteen [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	55.0
Derivative, Fair value	$ 0.2	[1]
Derivative, Interest Rate	1.12%
Derivative, Maturity Date	Jan. 01, 2018

[1] As of December 31, 2013 and December 31, 2012, derivative valuations in their entirety are classified in Level 2 of the fair value hierarchy. As of December 31, 2013 and December 31, 2012, we do not have any significant recurring fair value measurements related to derivative instruments using significant unobservable inputs (Level 3).