v2.4.1.9
Valuation and Qualifying Accounts (Detail) (Allowance for uncollectible Accounts, USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Allowance for uncollectible Accounts
     
Valuation and Qualifying Accounts Disclosure [Line Items]      
Balance at beginning of year $ 237,143us-gaap_ValuationAllowancesAndReservesBalance
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
$ 245,122us-gaap_ValuationAllowancesAndReservesBalance
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
$ 250,343us-gaap_ValuationAllowancesAndReservesBalance
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
Acquisitions     7,752us-gaap_ValuationAllowancesAndReservesReservesOfBusinessesAcquired
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
Amounts charged to income 381,337us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
298,711us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
243,377us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
Amounts written off 375,806us-gaap_ValuationAllowancesAndReservesDeductions
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
306,690us-gaap_ValuationAllowancesAndReservesDeductions
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
256,350us-gaap_ValuationAllowancesAndReservesDeductions
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
Balance at end of year $ 242,674us-gaap_ValuationAllowancesAndReservesBalance
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
$ 237,143us-gaap_ValuationAllowancesAndReservesBalance
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember
$ 245,122us-gaap_ValuationAllowancesAndReservesBalance
/ us-gaap_ValuationAllowancesAndReservesTypeAxis
= us-gaap_AllowanceForDoubtfulAccountsMember